A few question preceeding "Winter Build"

[Steveog]

I'm collecting parts for my 3xv1 rebuild. I'd appreciate some help with a few questions before I start a "Project" thread.

1 - I have access to a "Pro-Shift" up and down semi-auto shifting device. I have never seen an auto-shift device mentioned here. Is this a good or bad idea on a 2T? Pro-Shift is made in UK and my partner had it installed on his ZX-6, but when his bike blew a head gasket, his builder convinced him to use a "Trans-Logic" auto-shift. Pro-Shift was a $5000 system when purchased. It will be mine to use, gratis.

2 - I'm ordering Wossner piston kits and have been made aware that re-plating tolerances need to be "looser" (0.06), as forged pistons expand more than cast versions when they are up to operating temps. Also, warm-up with forged pistons must be approached with more deliberation. Please educate me as to how/if this info applies to my 3xv1.2. (FYI - Martin 77 has ported my cylinders and skimmed the heads. I also, now have a Toomey Dual-Core, TZ Radiator).

3 - What is the advantage to higher output coils?

4 - Concerning my new radiator, the designer (Ed Toomey) says, "That for track work, I should dump the thermostat, keep an eye on my temp gauge and use a blocking system to control air flow to the Rad. What is the ideal temp for a 3xv under load on the track? It "seemed" to run best at 55C (before spitting its crank bearing). The rad has a pick-up for temp gauge built in. Thoughts on these cooling system suggestions will be appreciated. Toomey is an ex-racer, tuned TZ's for their entire model-life and produced an AMA national champ in 2001.

That's it for now.  As always, thanks in advance for any knowledge/experience you can share.

[maccas]

The pistons should be slightly smaller than their cast counterparts out of the box. Just measure the clearance in the cylinder, I'd expect it to be 0.06mm as they stand to be honest. If too tight, get them honed until the clearance is correct. It won't be far away.

Regarding the radiator, I'd have to disagree with removing the radiator with your bike. It's not going to be in as high a state of tune as a TZ and a rad like that will over cool it without taping quite alot of it up. Removing the stat does remove clutter and a bit of weight, but instead I'd fit an rgv 250 thermostat. They open at 50 degrees instead of the standard 65 degrees. That will be much better in my opinion. The stat fits pretty well, it may just need a bit of a tweak to the body to fit in the housing.

If running a stat, you'll need to keep the temp sensor mounted in the stat housing, otherwise you'll get a false reading when the thermostat is closed!

Dan

[Steveog]

Thanks, Dan.

Your input on pistons is very helpful. Obviously, Wossners have been working for many here, I was just curious. I'm using a US company which specializes only in plating cylinders, so I'll pass along your advice about honing specs, but I'm pretty sure they've seen 3xv cylinder and Wossners before, as they were recommended by two trusted members, here.

The reason I went for the TZ Dual Core is we run in air temps up to 36C with 70-85% humidity in our summers here in the mid-western US. Track temps have been as high as 70C. Last year, my 3xv just fell on its face once we got into some afternoon sessions. It reminded me of how old air cooled 2T's would lose power once hot...only worse. I questioned the jetting, but a few plug chops showed the bikes performance when “hot” wasn't directly related to carburation. I chased that demon most of the summer. It was Phil M. who advised a big 4t or Dual-Core radiator when I run in those temps. When air temps finally dropped in September the bike came alive. I'm not disputing your opinion, as much as justifying mine. I asked and appreciate the input.

Will investigate the RGV thermostat. Yes, I'm familiar with the stat mount, having rebuilt mine...twice.

Have a good weekend.

Any opinions on semi-auto shifting would be appreciated. There must be a reason why they don't seem to be discussed here, although I've seen the sensors on the shift rods of older 500 GP 2T's.

[vinny]

Im not sure if you mean quickshifters like what most track  racers use or  airshifters like used in drag racing ?
Anyway here's my 2cents .
Iv used quickshifters for years and never had a issue .
Both me and my brother used Battle shifters on our honda rs 250 for 5+ years.
These are a very basic and reliable shifter all the 250gp boys in our class were using them and the only issues i ever heard of were small little things , wireing loose connections etc .
I Had a translogic on a zxr 400 for 6 years and no issues .
The translogic had a wheel sensor and every time you changed the gearing you needed to reprogram the shifter .
It had different lengths of ignition cuts for each gear  .
It is supposed to be easier on the gearbox that way but I can't really say. 
I'm currently using a zeel ignition with its built in shifter on my 3xv racebike and it's been working fine for the last year.
Once they are set up properly  id have no issue with using one .

[Steveog]

Yes, Vinny I was referring to a quick-shift system. Thanks for the details on your situation. The “Pro-Shift” cuts in for upshifts and has an “auto-blip” for down-shifting.

I’ve just ordered a Zeeltronics for my 3xv. Wondering now if I need the “Pro-Shift”? The auto-blip function of the PS for down shifting does seems attractive, specifically if I decide to go to premix.

[Martin77]

Not sure how the autoblip would work with carbs.. easier just to learn to do it yourself Steve

[Steveog]

Thanks, Martin. I've been shifting the old fashioned way for 45 years, just got curious when the "Proshift" device was offered.

My TD partner had the PS on his ZX-6. He said that with a push-pull throttle, one of the cables gets hooked to the PS. To your point, his bike is also fuel injected. The throttle pull on a 3xv with oil pump attached is relatively "heavy" compared to a modern FI bike. It would take a hell of a servo to make it all work.   

No matter how fast the bike shifts, its not as if the 1000's still won't blow past on the straights.

[jools]

I would just like to add a note of warning about removing the thermostat entirely.

Earlier this year on my TZ750 I left both thermostats out, for some silly reason, which actually led to overheating issues. Not major but over the course of a race with high 30's air temp and high humidity the needle was climbing towards the "uncomfortable" area. This is caused by too fast a flow through the radiator which actually reduces the cooling effeciency.
I should have, like I do with my 3XV, used restrictor plates which allow continuous flow at a reduced rate and give the radiator time to do its stuff. Simplest way to make these is cut the guts out of an old thermostat.

Most of bikes run around 60 - 65 degrees C or slightly cooler. The 750 was getting up around 90 - 95 degrees at the end of a 5 lap race. For now the thermostats will go back in.

[Steveog]

Thanks, jools. Your advice runs parallel with Dan's, I believe. He was concerned for me over-cooling. Either way, there seems to be good reason to keep the thermostat.

A TZ750 must be one hell of a ride. Do you you race or just scare the Hell out of all the 4T's on track days?

[Warwick]

I suppose there are a few variables to consider, and you'd maybe want to experiment with different set-ups to see what works best for you, Steve. I've used an RGV stat to good effect on a 3XV, but I've run my 3XV track bike without any stat for years. It's never been a problem for me.  I run it TZ/Sugo style - take offs from both heads fed direct to the two individual hook ups on the SP rad and a TZ capillary type temp gauge plumbed into the SP rad as it has the fitting for it. The bike Generally sits at 60 degrees or so in spirited use. Have had to tape the rad up a little once or twice for early morning sessions when it was especially cold or wet, but have always had to pull the tape off after a few laps - like a pukka 70s/80s GP hero! 

Stock coils should be more than up to the job if they are working well I'd think? And unless you're within a second or so of class lap record pace any kind of quickshifter is unlikely to be worth the hassle and cost perhaps? But then I'm old school and like to keep things as simple as possible for my little brain... 

 

[Steveog]

Excellent advice, Warwick.

Quickshifter first: When my 3xv locked, the next track day I was offered a ride on a "built" GSX-R 750 by the sponsor. Quite a treat. That thing had a GP pattern quickshift (up only). It was a lot of fun. Scary fast. But, I believe my ego was driving the question concerning a QS for my 3xv. That and one was being offered to me, but as Martin pointed out, the auto-blip won't plug and play with carbs.

I'm tempted to try the radiator as you described as "TZ Style". My big concern is, "I just spent a Butt-Load on new crank, porting, pistons and head-work. I'd hate to fook-up a brand new motor with "playing racer", when the purpose of this great Rad is our giving my bike a fighting chance in our Hell-on-Earth summers." Do I need the entire RGV housing and thermostat or just the internal unit? Suzuki lists the thermostat as a separate part.

The coils on my bike work as they should. I had it starting on first kick, hot or cold. Will not touch.

The actual "build" probably won't start for a few weeks. Getting my stuff back from Martin on Monday, but the cylinders still need repair and plating.

Thanks for jumping in. Your emoji with the "Afro" looks just like me in college. I rode an X-6 back then, redefining the term "Helmet Head".

[Warwick]

The RGV 'stat can be fitted in the 3XV housing. I'd imagine there will be many other 'stats that are compatible but cooler opening than the stock 3XV 65 degree unit too though, so it might be worth a bit if research if you can't easily find a good used RGV one locally? 

I'm as bald as a coot, so helmet hair is not a worry for me thesedays...

[yorkee]

you can also consider drilling the thermostat, so there is a smaller water passage provide consistent coolant flow similar as running no thermostat, except its limited by the size of the hole.  thermostat still open / close as usual to provide greater/less coolant flow depends on coolant temp.   

[SuperBee]

I drilled the stats on my TZ750 powered sidecar.

Allows a small flow to warm the whole cooling system gently and reduce the risk of cold seizure.

[Steveog]

Gents. I am interested in all solutions, But "drilling" where, how much and what drill size should I consider for my thermostat?

My 3xv will be track only. It will have Martin's SP spec porting/skimmed heads, Wossner (dual ring) Pistons, Dog Fight Pipes, Zeel CDI and stock 28mm carbs with stock, but higher flowing air boxes. I've been advised that my TZ, Dual-Core radiator may be "too much" and I will be have to block-off surface area in cooler ambient temps. NP. Most of our riding temps here start where you in the UK stop. You've seen our higher ambient temps earlier int this post.

Just a bit of more detail on how to adapt a an RGV thermostat, via drilling would be helpful.

The builder of my Rad recommends, dropping the thermostat altogether and using the TZ bung for a temp gauge to adjust coolant temps based on the individual day's temp, blocking the air-flow as would be appropriate to reach in 55-60C water temps.

That said, I'm very much interested in the adaptation of the RGV thermostat (or others) to my 3xv. Again, please provide details for drilling and modding thermostat.

Its all good as I approach a compete re-build this winter. 

Thanks, again for your input to this thread.