[DAD]

Originally Posted by MC@Performance Fab The fly by wire isn't your problem. All the late model stuff running 2 butterfly's are fly by wire, it helps the torque on those quite a bit.

Mac

The double butterfly throttle bodies are indeed fly by wire. The computer takes engine parameters such as rpm, map, and throttle position to open the secondary's at the proper speed to make the motor smooth and ridable. This is controlled by the ECM, for street riders they also must factor in the inexperienced rider doing something stupid and high siding the bike because they used too much throttle at a too rapid of an opening speed. (We called it grabbing a hand full.)

The racing ECM's have provisions for changing the action of the secondaries better suiting them for more experienced racers or by keeping them open all the time. We chose to remove the secondaries altogether and re-map the ecm accordingly. This helped a little in the case of the zx10r but then acceleration was never really a problem with the Kaw.

Yamaha YEC racing kits chose to do away with fly by wire system all together.

Here comes the whole can of worms all over the place.

Read and enjoy!!! The only thing wrong with YEC is Mr Engler makes a fix that is probably cheaper!!!! You just can't protect racers from them selves. http://www.yamaha-racingparts.com/do..._YZF_R1_EN.pdf

SEE page 57 & 60 of 96

Honest Dad himself

[Andrew Martin]

Ok. Now I'm totally confused. The throttle bodies (I have 2) don't look like they ever had more than one butterfly. The variable tubes on the set I just got seem to have a gap under them when raised.
I put the engine in a new car recently and pushed the rosson tubes down as far as they would go. I don't think they were right down before. Would this give me grief? How much power down low would I lose? We maybe talking up to an inch.
I have spoken to Shaun Barnett and he says go with montey's velocity stacks but my dyno guy is adamant I should lose the fly by wire.
This is an 08 r1.

[Andrew Martin]

And I'm not supposed to change gears by our rules as we have car engines running with us. Slipping the clutch sounds scary.
Thanks

[DAD]

Andrew

Yamaha does things a little different from the other bike builders.. They only use 1 throttle plate, that is a good thing, however it lowers restrictions in the intake track. Like I said they still have to make these things a little IDIOT proof to protect the rider. This is done with the computer controlling the throttle or "fly by wire" with computer commands. If you smash the throttle wide open the computer looks at what else the engine is doing and says "This guy is nuts, no way am I going to move that fast, he is getting ready to throw himself on his "ARSE", so using the good judgment programed at time of setting up the bike it does not open that fast and everything is just fine. Now a little better rider can open the throttle a little faster than a novice, and if he wishes to race and win he goes out and buys a $10,000.00 YEC Racing kit for his bike.

Like I said they do away with fly by wire all together and go back to the antique cable system. Now all that is left for you to do is figure out how to remove that stepper motor located on your throttle shaft and attach a bell-crank system in it's place. I would almost bet that an earlier throttle body will fit in the place of the new one. You might also have to replace the rubber boots on the head to get them to line up properly.

We race at a pretty constant rpm. The movable ram tubes were designed to help bike that had to operate smoothly from 1200 rpm's to 13000 rpm's and the length change helps out there. You probably operate from around 7000 rpm's to 13000 rpm's and the movement won't help much.

Remember short tracks with tight turns make the tubes long, long tracks with foot on the floor all the time short stacks.

Remember if you go to cables you are going to be way lean at low rpm's that is when the Dyno Man earns his keep.

Now get out there and do some searching, report back on what you find!!!

Honest Dad himself

[Andrew Martin]

The 06 fits with an angle grinder if you know what I mean. Looking at the spare throttle body I think I can lock the 2 sides of the throttle mechanism together and lose the electric motor.
It's going on the dyno anyway.

[DAD]

Andrew

the earlier throttle bodies have an adjustable couplers in the middle so that you can balance air flow at Idle. BUT race cars don't have to idle much and at flat out they will be balanced. I would try the older throttle bodies first and see what happens.

Computers aren't as smart as many people think.

Honest Dad himself

[MC@Performance Fab]

LOL....the two of you are confusing ME and I have a pretty good idea what I'm doing..............Andrew you do know that the 07-08 airbox won't bolt down to the 04-06 throttle bodies?

I'm thinking you are about to spend good money after bad....

[DAD]

Andrew

If you got it just use the old air box that should tell you something. Early air box probably about $50.00 ebay. Generally throttle bodies will interchange but sometimes you need the cylinder head boots also to match everyhing up. Works on Kaw's and I think Suzukie's.

Racing is experimentation and trying to out think your opponent, You can do it or wait for someone to do it for you!!!

I confuse a lot of people Mac, you sure aren't the first to bring that up. Just trying to stay ahead of the curve.



Honest Dad himself

PS. Mac did you click on the link in above post?