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wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 27 2008,22:27 This might get a debate started ?!   I was doing some research on Pure-2-Stroke-Spirit site last night, (I was bored !!), on the state of tune of stock barrels, & discovered that -00 barrels, (which have been fitted to my '93 RS), have a LOWER state of tune to the -50s that SHOULD be fitted !! The exhaust port duration on -00s is 184 degrees. On -50s, it's 192 degrees !! On the early SPs it's 196 degrees !! The transfer port duration on both -00s & -50s is the same at 118 degrees. So, I've discovered a previous owner has replaced the -50s for a set of -00s that have a lower state of tune !!  -00s are tuned to peak at 9,500 rpm, & the -50s are tuned to peak around 10,500-11,000 rpm . So, I'm guessing the '93 onwards models are strangled electronically ??, (speed limiter & -60 CDI ??), not by the porting. Was the '93 onward bikes speed-limiters set to trigger at a lower speed, (& hence revs), to produce the then new Japanese legal limit of 40 hp ??, (I can't remember), or was it still 180 kph ?? I'm trying to figure out how they capped them to 40 hp if it wasn't the porting !!    My -60 CDI has been replaced with a -40 at some point, probably the same time  the barrels were replaced !! I dug out my old 2 stroke tuning book, ( by the late John Robinson of Performance Bikes fame ), & have been studying it avidly again, hence my points above.                  Yours, confused, Wullie.     -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 27 2008,22:48 '93 onwards models have 40hp restriction. With -40 CDI you must have mechanical oil pump. Do you? -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 27 2008,23:04 Yes Alex, it has an "old tech." mechanical pump fitted. Was fitted by a previous owner, as was the -40 CDI, -00 barrels & -01 cyl. heads.                         Regards, Wullie.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 27 2008,23:15 The electrical oil pump is a nice thing. But for tuning with Sugo-Cdi you need the mechanical one. Look at my 3XV9 tuning: here You will have the right base for tuning. -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 27 2008,23:16 -50 barrels are SPR barrels, Wullie. Your 93 RS would've had -30 barrels and -50 heads. I've got a -30 kicking around somwhere, but if I remember correctly the ex on the -30s is a little bit shorter duration than the -00s. Hardly anything in it though. -------------- A garage overflowing with old stinkers... Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 27 2008,23:27 Quote (Warwickb @ Nov. 27 2008,22:16) -50 barrels are SPR barrels, Wullie. Your 93 RS would've had -30 barrels and -40 heads. I've got a -30 kicking around somwhere, but if I remember correctly the ex on the -30s is a little bit shorter duration than the -00s. Hardly anything in it though. No, '93 RS has -30 barrels and -50 heads. -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 27 2008,23:41 Bugger !!, thats twice I've been wrong this week !! I stand corrected. I'll put it down to fatigue. I was too lazy to dig my notes out, only got about four hours sleep last night, ( & it wasn't because of the Mrs. ) . Yes, I should have typed -30 barrels, NOT -50, sorry for the confusion.                          Yours, knackered, Wullie.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 27 2008,23:48 Quote (redandblue @ Nov. 27 2008,21:27) Quote (Warwickb @ Nov. 27 2008,22:16) -50 barrels are SPR barrels, Wullie. Your 93 RS would've had -30 barrels and -40 heads. I've got a -30 kicking around somwhere, but if I remember correctly the ex on the -30s is a little bit shorter duration than the -00s. Hardly anything in it though. No, '93 RS has -30 barrels and -50 heads. Yes. Typo in the original post, Alex. Damn my fat fingers! Do you have any dyno data for the '93 SP yet? -------------- A garage overflowing with old stinkers... Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 27 2008,23:53 Quote (Warwickb @ Nov. 27 2008,22:48) Yes. Typo in the original post, Alex. Damn my fat fingers! Do you have any dyno data for the '93 SP yet? No problem. Dyno data from my SP? Or from my '93 RS? -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 27 2008,23:58 Quote (wullie3XV9 @ Nov. 27 2008,21:41) Bugger !!, thats twice I've been wrong this week !! I stand corrected. I'll put it down to fatigue. I was to lazy to dig my notes out, only got about four hours sleep last night, ( & it wasn't because of the Mrs. ) . Yes, I should have typed -30 barrels, NOT -50, sorry for the confusion.                          Yours knackered, Wullie.   Don't worry about it, Wullie. It's great to see people actually getting stuck in a bit. And it's about time others started posting the results of their experimentation and paying for some dyno time etc. I've about run out of steam with it all myself. Been spending more time renovating an old CRM250 than thinking about the 3XVs recently... I will have the final evolution of the old modded -00 cyls motor (now with the TZ carbs) on the dyno at some point before it gets the TZ cyls slung on though. -------------- A garage overflowing with old stinkers... Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 28 2008,00:02 Quote (redandblue @ Nov. 27 2008,21:53) Quote (Warwickb @ Nov. 27 2008,22:48) Yes. Typo in the original post, Alex. Damn my fat fingers! Do you have any dyno data for the '93 SP yet? No problem. Dyno data from my SP? Or from my '93 RS? Lol. I forget that you have so many, Alex. Data from both would be interesting. Do you have the data in Dynojet format? Or do you use a different type of dyno over there? Which cyls are you running on the RS by the way? -------------- A garage overflowing with old stinkers... Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 28 2008,00:31 Ahh, I have talked with Hans two weeks ago. My 3XV9 will go on his dyno in january because he has to much work. Then I will ask for dyno file. See the link above, I use 3XV10 cyls for my RS. Got the cyls from Tom. By the way. He is Japan and still ok. -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 28 2008,01:34 Very nice RS Alex. Unfortunatley, I,m short of money. (who isn't) !! I'm trying to work out how much to lift the exhaust port by, using info in my tuning book to help, & to see if I need to raise the transfers at all, hence my reference to the port timings on 3XV6/9 -30, repeat, -30 barrels. I worked out I need to raise the exhaust port 1.5 mm, to match -30 barrels 192 degrees duration. Warwick, can you measure the distance from the top of the main & auxiliary exhaust ports, to the top of your -30 barrel for me, please, to see if my calculation is right, & I'll compare it to my stock -00 barrels when I get them off. I know raising the exhaust port doesn't always mean you have to raise the transfers as well, (on a road bike), but a faster engine speed requires a longer "blowdown" period for efficient scavenging of exhaust gasses, etc. I reckon the -30 main exh. port height will be approx. 26.5 mm. -00 is 28.0 mm from top of the cylinder. Oh !!, can you measure the WIDTH of the main exh. port as well, please, top AND bottom, to see if it tapers down or is parallel. If all thats required, to get approx. 50 hp at the rear wheel @ 10,500-11,000 rpm is to raise the exhaust port, & maybe a bit off the P.V. spools, I could manage that myself, (sorry Martin 77). There are a couple of machine shops locally that can skim the heads for me, after I've checked the squish of course !!   Just had another thought!! Can you measure the WIDTH of the 4 main transfer ports as well please Warwick, thanks. It's to see if they were WIDENED on the -30s, compared to the -00s. I'm just curious.           Yours, deep in thought, as well as knackered, Wullie.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 28 2008,12:08 I think your'e still confusing the -30 barrels with the -50's, Wullie . Ex' duration on the -30s is fractionally less than the -00s if anything as mentioned. Perhaps the SPR 50 barrels have less ex' duration than the earlier SPs though due to the diff auxililiary port and powervalve arrangement? You really want to be basing your porting on the earlier  -10 SP cyl's I reckon as they use the same drum type powervalve set-up as the R barrels.   If I can find the -30 barrel over the weekend I'll try to check the measurements for you, but the kit I have here is very rudimentary so they won't be precise figures in any case. Visually they look pretty much the same as -00 barrels, whereas the -10 barrels are very much more business like. The differences being very visible and quite substantial. You may well be able to get it up to 50 or so just by raising the exhaust a touch (assuming some decent pipes), but it's likely to make it a bit peakier than stock I'd think. My limited understanding of these things is that really you'd need to enlarge the auxiliaries quite considerably too to get better overall exhaust area, and that is very difficult without porting tools. And without the mods to the transfers you won't get the full benefit in any case I shouldn't think... -------------- A garage overflowing with old stinkers... Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Nov. 28 2008,12:17 Port timing doesn't directly dictate engine peak rpm, it also depends on pipe length (and carburation, ignition etc). )My TDR runs an exhaust port duration of 200 degrees, yet peaks at 9500) Here's the SP portmap I use; Anyway Wullie, widen the exhaust port to 41mm (chord), square the sides off a bit (keep the corners nicely rounded) and raise it 1.5mm (along with the sub ports if you can get in there), and you'll get more power at the top end. Don't chip off the plating! Back to top

nemesis Group: Members Posts: 10 Joined: Nov. 2007 Posted: Nov. 28 2008,13:27 Beautiful rebuild, redandblue.  Very inspiring! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 28 2008,22:01 Done a quick comparison of the -30 and -00 cyls for you Wullie. with the kit I've got here I can't really ascertain any real difference with any certainty. Ex port on the -30s looks to be a fraction of a mm lower, as do teh transfers but that seems to be about it.  And It'd take better measuring kit than I have to hand to be definitive really. Either way, if you do as Martin suggets you should see a small gain. Though as mentioned I'd think it'd feel a bit peakier to ride as I suspect you'd lose a little in the midrange due to the taller exhaust. Personally I'd suggest sending it over to Martin and getting the job done properly though rather than risk ruining your cyls . -------------- A garage overflowing with old stinkers... Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 28 2008,23:33 Got all the port timings from each models work shop manual tech. spec. section (Chapter 2), & made a note of them, hence my curiosity as to how the '93 onward models were capped to 40 hp. Martin 77, can I be cheeky & ask what cutting bits you use to grind open the ports & rechamfer them ??   Yes Warwick, I'm worried about damaging the NICASIL as well.    If it was steel liners, I wouldn't think twice about having a go. Blue-printed & gas-flowed my old 2MA, which gave it a healthy improvement over stock.    If it's possible, I'd like to have the pleasure of improving the power output myself. I'm a professionaly trained mechanical engineer, that knows how to use precision measureing equipment & tools, I've done it before & would like to try again. It'll probably be my last chance to have a go at tuning, you know what I mean ??       Yours, itching to get stuck in, Wullie.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 28 2008,23:40 Quote (nemesis @ Nov. 28 2008,12:27) Beautiful rebuild, redandblue.  Very inspiring! Thanks. If anyone is interested in modifying the temp. sensor, please ask. I can do it for you. -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Nov. 28 2008,23:42 Carbide/diamond burrs Wullie...search on ebay... Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 28 2008,23:51 Cheers Martin, much appreciated. You'll tell me now that the burrs cost as much as having you do the porting !!  If I do them, I'll be saving you some work,    or would you rather have the money. (Silly question with Christmas coming !!). How much is a set of burrs by the way ?? -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

STEPTOE Group: Members Posts: 158 Joined: Oct. 2007 Posted: Nov. 29 2008,01:14 Quote (wullie3XV9 @ Nov. 28 2008,21:33) Got all the port timings from each models work shop manual tech. spec. section (Chapter 2), & made a note of them, hence my curiosity as to how the '93 onward models were capped to 40 hp. Martin 77, can I be cheeky & ask what cutting bits you use to grind open the ports & rechamfer them ??   Yes Warwick, I'm worried about damaging the NICASIL as well.    If it was steel liners, I wouldn't think twice about having a go. Blue-printed & gas-flowed my old 2MA, which gave it a healthy improvement over stock.    If it's possible, I'd like to have the pleasure of improving the power output myself. I'm a professionaly trained mechanical engineer, that knows how to use precision measureing equipment & tools, I've done it before & would like to try again. It'll probably be my last chance to have a go at tuning, you know what I mean ??       Yours, itching to get stuck in, Wullie.   I'm a professionaly trained mechanical engineer sorry to be an ass, but surely then you would know the bits and technique required to do this work.... Im not a trained M E and I know , but I also know my own limits. -------------- viva la revolucion  !!  suck squeeze bang blow Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 29 2008,01:47 Valid point Steptoe. Trained mechanical engineer, yes, trained machinist, no !! I replace/overhaul & test aircraft mechanical components & assemblys. No machining or manufacture in my line of work. Blue-printed my 2MA in '88 when I was an airframe mechanic in the R.A.F. The cyl. heads were skimmed by the base workshops I was stationed at back then. I had access to the necessary tools, bought & studied a tuning book, worked out what I could & couldn't do myself, had a go, & thankfully didn't cock it all up !! I DO know my limits. Blue-printing/lightly tuning NICASIL coated bores MIGHT be a step too far for me, but, with the right tools, & some care, it is POSSIBLE. Would just like to have a go at doing it myself again, thats all.  No offence taken, by the way.                       Regards, Wullie.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

jools Group: Members Posts: 1221 Joined: Oct. 2005 Posted: Nov. 29 2008,11:04 Quote (redandblue @ Nov. 28 2008,21:40) Quote (nemesis @ Nov. 28 2008,12:27) Beautiful rebuild, redandblue.  Very inspiring! Thanks. If anyone is interested in modifying the temp. sensor, please ask. I can do it for you. Alex why do you mod the temp sensor (out of curiosity) ? Jools -------------- "The only thing worse than being talked about is not being talked about...." oscar Wilde Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Nov. 29 2008,11:59 Quote (wullie3XV9 @ Nov. 28 2008,21:51) Cheers Martin, much appreciated. You'll tell me now that the burrs cost as much as having you do the porting !! The burrs cost as much as it would for me to do the porting anyway wullie.... Nah only joking, like I said, look on ebay   The question is also, have you got a grinder that'll reach into the places you want to go? I'm all for people having a go at porting, as long as they do it carefully and with consideration, then blame no one else if they cock it up. We've all got to start somewhere afterall. Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 29 2008,20:42 Martin 77. We have slim pneumatic powered drills with 90 degree & 45 degree angled heads & the small collets to grip various diameter twist drills, so they may be able to grip the burrs if the shanks not too big in diameter. I'll have a look on e-bay to get a better idea.  And yes, I am man enough to admit when I cock-up !!                                 Thanks again Martin.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

STEPTOE Group: Members Posts: 158 Joined: Oct. 2007 Posted: Nov. 30 2008,01:44 Quote (wullie3XV9 @ Nov. 28 2008,23:47) Valid point Steptoe. Trained mechanical engineer, yes, trained machinist, no !! I replace/overhaul & test aircraft mechanical components & assemblys. No machining or manufacture in my line of work. Blue-printed my 2MA in '88 when I was an airframe mechanic in the R.A.F. The cyl. heads were skimmed by the base workshops I was stationed at back then. I had access to the necessary tools, bought & studied a tuning book, worked out what I could & couldn't do myself, had a go, & thankfully didn't cock it all up !! I DO know my limits. Blue-printing/lightly tuning NICASIL coated bores MIGHT be a step too far for me, but, with the right tools, & some care, it is POSSIBLE. Would just like to have a go at doing it myself again, thats all.  No offence taken, by the way.                       Regards, Wullie.   cheers wullie, it actually sounded a lot worse when I read it back than it did as I said it,,,, if you get me. well, you deffo sound like you know your stuff anyway, so hope it goes all OK for you, -------------- viva la revolucion  !!  suck squeeze bang blow Back to top

redandblue Group: Members Posts: 95 Joined: Oct. 2005 Posted: Nov. 30 2008,04:23 Quote (jools @ Nov. 29 2008,10:04) Alex why do you mod the temp sensor (out of curiosity) ? Jools hmm... to fit into the radiator... maybe... -------------- 2MA, 3MA3 black, 3MA3 white, 3XV6, 3XV7, 3XV9, 5KE2 my site: http://www.pure-2-stroke-spirit.info my forum: http://forum.tzr-scene.info German TZR Forum Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 30 2008,15:41 Just double checked the 3XV6 & 9s port timings again & it definatley has exhaust port timings as opening at 84 degrees A.T.D.C & closing at 84 deg. B.T.D.C., (power valves fully open) Transfers opening at 121 deg. A.T.D.C & closing 121 deg. B.T.D.C.  3XV1 & 4 exaust port timing is 88 deg. A.T.D.C & 88 deg. B.T.D.C. Transfer timing's the same at 121 deg.  Is it a printing error for the 3XV6 & 9s exhaust timing, or is my arithmatic skills that bad ?? !!     Could some one reassure me, please !!                          Many thanks in advance, Wullie.             -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Nov. 30 2008,22:35 OK, got some (slightly) better measuring tools together (er, and actually pulled the head of the -30 barrel too to allow me to get in better ). Looks like the quoted figs are probably right. In spite of what my eyes were telling me yesterday, the -30 main ex' port does in fact look to be a bit taller than the -00 and also extend a little lower. I'm measuring the -30 at about 26.5 mmm from the top of the bore, while the -00 is about 27.5. Importantly though there's no difference in the subs/auxiliaries which are quite important in terms of giving you greater overall area. My -30 cyl also looks to have had a little light work on the ports too at some point, so I can't be 100% that the port dimensions of this barrel are stock. Apologies for the confusion. It's all a bit academic really though, as you want to be basing your porting work on the early SP cyls I'd say if you want to see some genuinely noticeable gains. -------------- A garage overflowing with old stinkers... Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Nov. 30 2008,23:57 Thanks for persivering Warwick, much appreciated !!     I cant be sure, but I think I read on here somewhere that all Stan Stephens did to 3XV barrels was lift the main exhaust ports & just tidy up the others on a stage 2 tune, & claimed 52 hp !!    I've been trying to locate the particular thread in question, with no luck so far.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Dec. 01 2008,13:18 To be honest, I'd think that a set of decent pipes alone would prob take a fit, stock 3XV up to around 50 or so, but it wouldn't be a very noticeable improvement over stock, as a good stocker should be making 45 or so. Mine made 50 with stock -00 porting and Cdi, Nikons and a pair of TZ pistons (which lower compression of course being flat-topped, but also lower friction losses) years ago, but still felt somewhat strangled at the top end. I'd say that you want to be aiming for 55 or so at least to make any tuning work worth the hassle. Mr Stinkwheels has some Stephens stage 2 barrels I think, so he can prob confirm the spec. -------------- A garage overflowing with old stinkers... Back to top

Mr stinkwheels Group: Members Posts: 206 Joined: May 2006 Posted: Dec. 01 2008,14:09 Hello. Yes I have some Stan Stephens stage 2 barrels. From looking at the ports, all I could see was he had raised and re-shaped the top of the exhaust port a bit, not a lot of work for the money he charged, he also skimmed the heads. But having said that, I did see a fairly nice increase in power over the stock ports. The early dyno runs I had were crankshaft reading not rear wheel reading, so taking into account that the Yamaha claimed 45 bhp from a std bike, is crank reading, I thought my results were fairly good. So if I can remeber right, just bolting the Lomas pipes on gave me a crank reading of 53 bhp. Then with the Stan Stephens tune we saw 59 bhp at the crank, so roughly a 6 bhp gain from just the tune. 59 bhp at the crank equates to roughly 54 bhp at the rear wheel. I had Martin77  tune my other barrels to SP spec for a lot less then Stan would charge for his work, and in my opinion got a neater job from Martin and a lot quicker. I had this set up dyno tested this time rear wheel reading, on simular equipment to what everyone else seems to be using  and saw 58.5 bhp at the rear, and stronger through the mid range too. That would give me a crank reading of about 63 bhp. So simply bolting on a good set of pipes and getting the ports to SP spec saw about 18 bhp increase over std Yamaha claim. Carburation changes did not make any improvement to top power but did smooth the power curve out. Everything else on my bike is standard -00 cdi and 28mm carbs. Hope this helps Martin. Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Dec. 01 2008,15:09 I think the 45 fig. is actually the 'official' rear wheel figure, Mr. Stinky. Unlike with most bikes, when a bike has to be restricted by law there's probably no point in quoting an exaggerated crank fig. in the official literature as you want the bike to be making as much at the rear wheel as it is legally allowed to - Jap market RGVs and NSRs etc all make pretty much bang on 45 at the wheel. I don't know for certain that this was the case with the 3XV though, and I only ever dyno'd my R once when it was bone stock, but it duly gave just a smidge under 45 rwhp on a dynojet rig. It was about 8 years ago, but I'll try to dig the scan out later. Edit: OK found it: Bike was bone stock and the motor must have been pretty tired as it was on it's original pistons and rings at about 20,000 kms - it spat a ring out a couple of months after this run in fact, lol This is the same bike, but running TZ pistons and Nikon pipes a couple of years later: Doesn't 'prove' anything of course really, but it may be of interest. The main problem is that it's not really easy to campare the runs directly very easily as I only have papaer prints - and the prints both show power against rear wheel mph (4th gear, both on stock gearing if I recall - red trace on teh lower scan is through the gears obviously, blue trace is the static 4th gear run) rather than rpm. So what would be really useful is some raw dynojet data for a fit but completely stock 3XV so that we have a useful 'base run' to plot directly against other, more developed, runs using the dynojet Winpep software. Anyone with a fit but completely stock 3XV R model fancy running it up on their local dynojet rig and sharing the data for 'the cause'?  I have a stock SP I could run up I suppose, but I think the stock SP curve is a bit different to the stock R curve, and as so many are developing the R it'd perhaps be better to have the R data really. -------------- A garage overflowing with old stinkers... Back to top

Mr stinkwheels Group: Members Posts: 206 Joined: May 2006 Posted: Dec. 01 2008,23:02 Hi Warwick. I was told by the Yamaha dealer down here that Yams power claims are from the crank, as and I quote " the figures are more impressive from the crank". I was reading up on my R6 at the time in the shop, when I mentioned about the claimed 128 bhp, and was told I would not see that on the dyno from a stock R6 for 2 reasons, 1) being the forced air intake would not be in affect as the bike is not moving and 2) the back wheel reading is always about 15% less than the crank reading but I shoulds see 112 bhp. It would be good if we could get conclusive proof, if anyone knows for sure what figures we should believe. Hope this helps. Martin. Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 01 2008,23:17 "Anyone with a fit, totaly bog-standard R able to take it to a DYNOJET for a base figure run" Ehm... Sorry, it can't be me, my bog stock RS motor is now on a bench !! Took the heads off today, the piston crowns & the combustion chambers are as black as coal !! Probably a result of the oil pump being set WAY too rich, as delivered.    Adjusting the pump was the first job I had to do, as it was laying a smoke screen when cold !! Both bores look in good condition, no chips, pits or scoring, & you can still see the honing cross-hatching as clear as day.    The port windows & power valves are completely untouched as well.    The only downside is lots of "blow-by" in evidence. Some on the bore, but most on the pistons. Looks like I'll have to fit the new pistons & rings. Hopefully get time to check the squish clearances tomorrow, then I'll whip the barrels off & check the ring gaps, etc. I'll make up my mind about tuning once I know what state the crank's in !!  Hopefully, I can get another few thousand miles out of it.   If I have to rebuild the crank, the tuning will have to wait.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Dec. 01 2008,23:18 Yes, as I said, they all do that for bikes where legal restriction isn't an issue, but where it is then to do so would, I suspect, be a real sales disadvantage if competitors were using rear wheel figs? Don't they have a 100bhp limit in France? I wouldn't be surprised if the R6s sold there are quoted as 100bhp and make pretty much exactly that on the roller too... As discussed though it'd be really useful to have some raw data from a good stock 3XV on a dynojet rig so that we can feed it intop the winpep runviewer with other runs to give ourselves a useful baseline for direct comparisons. There are plenty of stock ones out there. And plenty of owners who benefit from this forum too. So come on fella's take your stocker for a turn on the roller and we can put this one to bed - and we'll have some really useful baseline data too... -------------- A garage overflowing with old stinkers... Back to top

jools Group: Members Posts: 1221 Joined: Oct. 2005 Posted: Dec. 02 2008,07:32 I'm not so sure Warwick - by bog standard 3XV put out 37 at the rear wheel before I started playing around. (That was even with the offset key in ) Japs always use the crankshaft for measurement - I think it is stipulated in their constitution !! The authorities were very hot on this and there is no way they would be stupid enough not to miss that old chestnut !! You must have had a good one Wazza or you found a good dyno - (lol) thats all I can say, maybe it was a blueprint... -------------- "The only thing worse than being talked about is not being talked about...." oscar Wilde Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Dec. 02 2008,12:40 Trust me, it was a bit of a knacker, Jools (still is really, lol) Those two runs were on diff dyno's too. Perhaps your's was just a bit of a sick one? I remember your original curves looked to drop off a bit earlier than they normally would - perhaps a result of the advancer key? None of this matters of course, but really, as I said, it would be useful to have some new, raw data from a good stock R in dynojet format so that we have a base for comparisons - as much to assess losses lower down as gains at the top of different set-ups. I'd have to add that pretty much every stock Jap' market RGV or NSR dyno I've seen was pretty much bang on 45 too though, so I'm guessing they must have been quoting rear wheel figs? Who knows? -------------- A garage overflowing with old stinkers... Back to top

jools Group: Members Posts: 1221 Joined: Oct. 2005 Posted: Dec. 02 2008,21:45 I am gonna call you Mr Squiggle from now on   Coz you always pull graphs out your hat   (thats the nickname for Gary McCoy too, if you didn't already know) -------------- "The only thing worse than being talked about is not being talked about...." oscar Wilde Back to top

skinuthbilly Group: Members Posts: 209 Joined: April 2007 Posted: Dec. 03 2008,01:14 i thought his nickname was lab rat!! Gary MCcoy on the red bull 500 yam,my favourite rider/bike of all time...... Back to top

jools Group: Members Posts: 1221 Joined: Oct. 2005 Posted: Dec. 03 2008,04:02 For those not of antipodean location - Mr Squiggle is an Aussie kids TV pencil puppet that draws black lines everywhere - just like mcCoy did on the red bull yam.......... -------------- "The only thing worse than being talked about is not being talked about...." oscar Wilde Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 06 2008,01:27 Here's an update. Having now removed the cylinders, they both have untouched / virgin ports.     Both my -00 barrels main exhaust port top edges are bang on 28.0 mm from the top of the cylinder. I've also decided NOT to do anything to the ports. The problem being gaining proper access to the auxiliary exhaust ports, they're smaller than I thought they'd be !!  Checked the squish on each cylinder head. the L/H head is 1.25 mm, the R/H 1.20 mm, (rounded down to nearest 0.05 mm).  I thought they would be around 1.4 - 1.6 mm ??  ( My old 2MA was 1.6 mm before it was skimmed !! )  Would it be O.K. to skim 0.2 - 0.3 mm off to bring it on or just below 1.0 mm ??  (I asked for 0.8mm to be skimmed off my old 2MA to bring it down to 0.8 mm optimum). -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Dec. 06 2008,12:02 Yes... anywhere between 0.7 and 1mm would be OK for the squish. You can still raise the main exhaust port to get more top end power regradless of not touching the sub exhaust ports....you know you'd like more power, so why not do it? Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 06 2008,15:03 Thanks Martin. I was thinking of getting the SP Cylinder O ring grooves cut at some point, hence why I mentioned a squish clearance of 1.0 mm, to allow for the removal of the standard metal head gasket after they are cut, which is 0.2 mm thick, yes ??, leaving a squish clearance of 0.8 mm.   I'll have another think about porting. I can get to the top of the transfers & the main exhaust ports no problem with the tools available to me. I just need to get some burrs.   Thanks for the encouragement by the way.     -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Dec. 06 2008,15:30 If you're not planning on taking it apart often, then there's no point having O rings instead of the gasket. Top ends can be removed leaving the head attached to the cylinder, and even if they do need to be split it's possible to re-use the gaskets (with alot of care and high quality gasket compound). Back to top

Warwickb Group: Members Posts: 1911 Joined: Sep. 2003 Posted: Dec. 06 2008,17:29 Seems like a wasted opportunity to not sort the cyls out while it's apart really, Wullie. It's worth remembering that the SP port dimensions and timings/durations are not really that radical - they are just what the R would have had too if Yamaha hadn't decided to port the R cyls more conservatively to make a grunty, but top end power-limited, motor. 3MA1 porting for example is far more radical than the 3XV-R. I'm with Martin: if you want more power at the top you'll need to get the grinder out. Optimising the squish might give you a bit more zap at the bottom, but you won't see any meaningful gains at the top without some port work... Of course, if you're happy with 45 ponies, then leave it as it is, but believe me there's a big, big difference between a stock R and one that's working as it should   -------------- A garage overflowing with old stinkers... Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 06 2008,17:29 That's a very good point Martin. As I've said elsewhere, after this overhaul, I dont want to remove anything for a couple of years !! ( Next top-end rebuild ).   I'll live with the coated metal head gaskets then.   Warwick, If my crank IS rebuildable, I WAS seriously considering getting Martin to port the barrels, It all comes down to money I'm afraid. Still a chance I MIGHT need it for a NEW crank. Don't want to "jump the gun".   Martin would £125.00 quid cover porting & sending back my barrels, after they're done ??  If so, it would be Jan./ Feb. at the earliest I'd send them down, if your not too busy then. (After the Christmas rush, don't want to take a chance on them getting lost Post / Parcel wise !!)                 Thanks again, Gents.     -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Dec. 06 2008,18:45 £125?....fine by me (I wouldn't ask for that much in the first place, but if your offering.... ) Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 06 2008,22:36 Martin, are you up for a bit of haggleing ??,  or have I shot myself in the foot with my first offer !!     -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

martin77 martin77 Group: Members Posts: 453 Joined: Sep. 2003 Posted: Dec. 07 2008,12:25 Maybe....check your personal messenger Back to top

wullie3XV9 Wullie3XV9 Group: Members Posts: 293 Joined: June 2008 Posted: Dec. 07 2008,16:07 Martin, have replied to your PM, check in your PM.  Many thanks.   -------------- Just when I'm about to make ends meet, someone moves the ends !! Back to top

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