3xv: Project Phoenix

[Warwick]

That looks ideal, Steve. The adapter will fit directly in the TZ copy rad, yes?

[Steveog]

Yes. Thanks. The rad mount thread is perfect. The sensor is a bit tough to make purchase in the mount. I was warned to not kink the cable, keep it smooth when finishing it up. When it got it here I thought it was misaligned, but it was just reading the air temp. HA.

The whole gauge system is passive, requiring no power or extra wiring. Need to fab a short-term mount. I don't want to bugger up the stock clocks, as someone might want them.

Steve

Have a good weekend.

[James P]

Yeah. I'm liking the DIY idea...Because I finally got that throttle cable mod to behave, I already feel like Irv Kanamoto. Well, not quite, but it's easily the most complex sub-assembly on the whole bike or any bike I've ever worked on. Quite diabolical. I've included a pic of the finished cable. Very smooth. No catching.

I'm going to try what you've suggested. I've got the aluminum and gasket material from slapping together the oil pump cover. Seems I could get almost any standard cable mount/adjuster to stand-in. There's that lump on the underside that collects the spring, but that could be a separate piece, threaded through and held with the cable mount.

Wonder why one of our fellows here with a 3-D printer hasn't tried to make this part? Its not listed by Yamaha as a part and it would seem that more than a few of us might want to get rid of the TPS. There is a market it would seem.

Always good to know you're following my antics. Thank You.

Steve

Steve,

If you want to proceed with the 'make-your-own' carb top (great idea from Warwick!), you could try using aluminium plate 6-10mm thick. For the spring spigot, you could use an M14 bolt (with a portion of the thread turned down in a lathe to about 11-12mm diameter, to make a smooth spigot...and perhaps the height of the bolt head reduced as well) screwed into your home-made top (which would be drilled and tapped M14 to suit) and secured with Loctite or Araldite. While in the lathe, this bolt/spigot could be drilled and tapped for the cable adjuster.
A fine-thread M14 bolt would be best and you may be able to find a drain plug which fits the bill (I have Suzuki 09247-14025 to hand and it looks like it would work - thread is 19mm long, same pitch as a spark plug).

If you want to find something ready-made in the USA, there were a few models of Suzuki RM80 from the early to mid 1990s equipped with Mikuni TM28 carbs. The top from one of these will fit the 3XV TM28SS.
As a last resort, you could perhaps cut down the standard 3XV TPS housing to make a plain carb top...

I infer that most makers didn't supply carb bodies, tops and float bowls separately (at least not from the 1980s onwards) - perhaps they reasoned that if you need one of these parts, you probably need a whole new carb! Having said that, I have sometimes come across new OEM parts in packets which are not listed separately in parts catalogues .

Let us know how you get on.

Regards,
James

[Steveog]

Thanks, James. Great ideas. Solid thinking. I may go your route. But...

As Karma (coincidence) may have an effect here, I just happen to have a 1986 RM80 with a VM28 carb. I checked the specs and the carb cap is listed, but NLA through Suzuki (this is true for all years of the RM80.) But, if I cannibalize mine, the issue may be solved...quickly. I can easily cut a new gasket.

My main concern is control of the air jets, which my Zeel can handle, but with little time to find a dyno before the next track day, 8/10, I may cause a problem with jetting for the sake of convenience.

Lots of changes at once. New rad and gauges. New Ignition. Eliminating TPS. Setting up proper jetting for a very fast track in high heat and humidity.

I'm willing to try, but all the experts here say, "One thing at a time."

Maybe the rad, Zeel and dialing in the jetting are good for 8/10 and I hold off on eliminating the TPS until that test is complete.

Thanks again for your wisdom. Much appreciated.

Steve

[Warwick]

I wouldn't worry unduly about the varible air jet system, Steve. You could test to see how much difference they make on your set-up by disconnecting them electronically though? Disconnected in this way it simply leaves the central jet in the VAJ block open - effectively giving you a fixed air jet - which is what the bike would have had if Yamaha weren't trying to get the bike through emissions testing for bike homologation by leaning it off at part throttle loads.

If it seems a little rich at part throttle with this set-up you could experiment with a slightly bigger fixed air jet? Anyway, the impact is not especially significant (when running a similar set-up to yours I simply had them disconnected electronically), but the quick test suggested would allow you to get a better idea of the effect they have.   

[Steveog]

I feel as though I should have know this, Warwick. I spent the winter reading the Forum and all I remember was that to eliminate the VAJ, the main air jet had to be relocated into the carb bell-mouth. Disconnecting is far easier and changing jets (if needed) would be also be much more simple than digging into the carb. Also saves the time of a tricky mod. Only 12 days until Atlanta. One of the most difficult pieces of asphalt in the US.

(Mystery rider from You Tube) 11&vid=344aab4c8129d9201ff35ff3b938e045&action=view

Yeah, I know the big 4T's will eat my lunch on the straight pieces. But, it should be fun. Bucket List Stuff.

Thanks for your tech tip. Spot on.

Steve

[Warwick]

Yeah, certainly worth a quick experiment I'd say. Had I stayed with the 28mm carbs I would have probably gone over to a fixed air jet fitted directly in the bellmouth myself, but a jet in the VAJ block - or directly in the rubber pipe itself if you decide to ditch the blocks themselves later - performs the same function.    

[busa1300]

Atlanta...thats a long way to travel for a track day.
Or is there some other activities going on in the area as well?

[Steveog]

Warwick - Yes. For the Atlanta Track Day, I'll just unplug the VAJ. Good/reassuring tip. Thanks

Busa - Yes. It's a three day trip from our Shop. I'm 69. My partner just turned 70, today. This is a team effort for us old guys. As I said, "Road Atlanta is Bucket List."

It's not as if we are wealthy and just jacking-off. We've been friends for almost 50 years. Riding street until 2018. Fortunately, we're still competent on the track.

The day will come...sooner than later...when that's no longer true. Much as when we were when 19..."take it while you can get it" is more true now than then.

I've got pictures of our truck and bikes if you're interested. Just PM me.

HA. Prayers are also welcomed.

Steve

[busa1300]

I understand, was just wondering if there was something about that track in particular. 
The bucket list is something I have been starting to concentrate on myself.....heading to Bonneville next month...
All my old riding buddies are either on Harleys now, or crashed back in the day and gave up riding...(actually almost all of them crashed at least once)

Good luck on your trip, hope you find what you are looking for on that historic track 

[Steveog]

Bonneville. Now, that's a trip in the literal and figurative sense of the Word.

I guess, the local racers have spoken of it in such hushed tones for so many years that Road Atlanta has become its own legend. That and the fact that Lawson, Spencer, Rainey and Schwantz all raced there during their AMA Superbike years. Also, guys such as Hayden. I've got autographs of some of those older guys, (HA...They're all younger than me), but got to know Nicky, personally. Owensboro, KY is only 30 miles from here.

We went to Mid-Ohio last year. Great track layout for a 2T, but the surface has been allowed to deteriorate. Neither Moto-America nor Code's Superbike School will go there. It's unridable if even marginally wet. So Atlanta got the nod this year.

I realize its all a bit futile on a small 2T, but ...

Good luck on the Salt. That's got to be fun.

Steve

[Steveog]

Made some progress on the mods today. Fabbed up the mounts for the TZ pattern, dual-core radiator and roughed in the hoses. Yes, I know I need hose clamps. HA.

I picked those hoses because of their flexibility. They need a bit of trimming, but I love the look and lack of clutter.

Not silicone.

Steve

Edit (two hours later): I just realized the frame-mounts look like PVC. They are Delrin (Polyoxymethylene), sourced as a 1" rod, cut and drilled to fit. The lower mount will be re-enforced with polycarbonate. The upper edge of the rad will get a thin rubber bumper to avoid touching/vibrating against the frame.

[Steveog]

Spent most of the day fabricating. The VAJ block was probably a lot of work for no good reason. But, they are both now unplugged and the plug mounts sealed.

Yes, Warwick. I know it would have been much easier to stick the primary VAJ jet in the rubber vac line feeding the carb, but I just got into building this mod. Pride of ownership and all that.

James. I did cannibalize my RM 80. The cap worked as promised. Thanks for the heads-up. I need to drill out the female threaded cable adjuster mount in the cap to accept the adjuster from the TPS. I'm using the stock cables, so the cable length should be close using the swiveling piece from the TPS.

Working toward getting the carbs finished, then adding the Zeel.

Only one needle clip was lost in today's activities.

Steve

[Warwick]

Have you done a quick test run with the VAJ blocks disconnected, Steve? If not have you left things so that the electrics can be quickly and easily plugged back in if you find that on your set-up it doesn't work so well without the VAJ system working? I'm thinking that as you are still running pretty rich on the mains the reduced mixer nozzle air intake might make things a bit lumpy with the current jetting?

Will you have the time to experiment with jetting a little at your next trackday? 

Rad looks neat. Overkill for now technically perhaps, but allowing the removal of the clutter of the thermostat housing is always good for motor access. You can always use a bit of tape if the motor is not getting warm enough on colder days of course, but I've rarely found this to be a problem with an SP rad running direct head feeds - and it's much cooler over here generally of course.       

[Steveog]

Yes, Warwick. My mod is pretty much "Quick-Change", except re-installing the TPS is of course is a bit fiddly. I'm hoping that I can eventually teach the Zeel to control the VAJ's.

No tests, yet. Hopefully, this weekend.

Understand on the Rad, but I've rationalized, that it's easier to add heat than take it away. That said, I just heard it was at least 15 degrees hotter in the UK yesterday, than here. That's unusual, but I'd be interested if other 3xv owners have experience "over-rich" running in you current weather?

Yes. Cleaning up the engine bay is rewarding. Now, to get the throttle and carbs sync'd up. That could require some modding.

As always, thanks for your insights and sharing experience.

Steve