Jetting Guru's....

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Cammo
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Re: Jetting Guru's....

Post by Cammo »

Keihin main jets to suit Honda OEM (series number is above somewhere).
"It's just a ride" Bill Hicks
air
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Re: Jetting Guru's....

Post by air »

Just noticed you mentioned it bogs with a headwind. It may not be the same, but i've come across more than a few people on here with the same problem.
The rubber sheeting that runs under the front of the head (in front of the airbox snorkel) must not be removed, if it is, the fueling is affected.
Had the same problem myself which i attributed to my own jetting setup, after replacing the sheet so it covered over that V section of the frame, no more bogging.

For my own part, i'm running an RVF with a full tyga system, 112.5's all round, 1 shim to each needle, pilots set 1/4 out from stock and the slides drilled to 2.5mm. As its a full system i never expected it to be perfect, power has been lost down low to a small degree and theres a very small almost unnoticeable flatspot if you hang around 6k. Apart from that it pulls well.

Been 'at it' for 3 years now on and off so i have a vague idea of how to jet it properly.

*** Read your post properly, the sheet is still in place....
Goinphaster
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Re: Jetting Guru's....

Post by Goinphaster »

Just replaced all the main jets with 112's all around, and what I think were .5mm shims under the needles (there was already a shim/washer under the needle that is thinner than what I added, I left it there and added the new ones). the carbs look pretty good, i did a quick check of the float heights and they were good too. I'll post up a photo about the foam in the intake snorkel later, at least where it is supposed to be. hopefully when I make the test run it all pans out.
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Re: Jetting Guru's....

Post by Goinphaster »

OH WOW!!!!!!!!!!!!!!!!!!!!!!!
I don't think my RVF ever ran that good when I first bought it! She pulls pretty good through out the rev range, any other gains will have to be done on a dyno and with a skilled technician. I am hoping one day to have G-Force tune it for me but they seem ever busy. Not that I can blame them- they are working hard in the right direction. While the bike was apart I took the time to change the front calipers out with 954RR gold calipers. My brakes are definitely more responsive, and have a better feel to them. My only problem now is figuring out how to stop the pulsing. I haven't even broken in the pads yet, and I think I can still feel the pulse. The pulse isn't associated with the wave pattern pulse that's common with wave rotors. It's a single pulse like they are possibly warped:( If anyone can help shed the light on what I can do to check and make sure the rotors are good would be a great help.
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Re: Jetting Guru's....

Post by Cammo »

Good result mate.

To check the discs for truth, you can jack up the front end and just hold a pencil or similar against the spinning disc, any runout will show up.

I have had a pulsating lever due to having some air in the lines at the m/c end, maybe another spot to look if the discs check out fine.
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Re: Jetting Guru's....

Post by Goinphaster »

Maybe a timeline and some more detail will help with this mysterious brake problem....
1- purchased the bike used in Japan. It sat for a little while outside with no cover, due to logistics.
2- when I could finally ride it, I noticed that the front brakes were pulsating. purchased wave rotors (they were only a few quid/dollars more)
3-purchased brembo calipers with adapter plates, they were o.k., looked good.
4- didn't have too many problems with them until I came back to the U.S. I think it was because I never had to really use them hard in Japan, so I never noticed a problem.
5- removed the brembo calipers and reinstalled stock calipers. suspected that the brembo's wouldn't bleed all the way, wasn't impressed with performance, many other stock bikes had better feel. glued some sand paper to some brake pads, installed them in the calipers and "cleaned" the rotors by spinning the wheel to remove any surface build up from pad to rotor rust (from all the sitting).
6- While at a Moto GP race I talked to some Galfer tech's about my problem and they said to make sure the rotors aren't mirrored. My rotors were mirrored so I changed them to un-mirrored. problem seemed to go away, but slowly came back.
7- just recently put the 954 calipers on, and cleaned the rotors again. reason for changing calipers was looks, and the fact that I am fairly certain that the stock calipers were sticking/dragging.

I need to ride it some more and put it through it's paces before I go drastic, but I can't help but feel that there might be a bigger underlying problem. that being said, I can't rule out the rotors (Pencil method works, but I need definitive numbers), so I can't move on to search for another problem. also I have a bleed port on the M/C banjo bolt. multiple belleds resulted in no air bubbles.....
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Re: Jetting Guru's....

Post by L.Svedberg »

A brake disc can develop metallurgical changes; if overheated severely on one single occasion, or if brake pad material residues have transferred onto/into the surface of the disc. This can cause the steel or iron to transform partially (in spots) into something called martensite, which is way harder than the surrounding steel/iron. Once this has happened, it's nearly impossible to make the disc ever work properly even if you'd have it ground or blasted, as these changes go deep. The sensation will be a pulsating feeling, as these spots offer different coefficient of friction compared to the rest of the disc. This may be caused by improper bedding in of new pads, or incorrect pad material,and the solution is to replace the disc.

I seriously doubt that any master cylinder, or any caliper can cause a pulsating feeling, no matter how badly bled they might be. If your discs are straight, consider the above alternative.

/Lasse
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Re: Jetting Guru's....

Post by Goinphaster »

L.Svedberg wrote:A brake disc can develop metallurgical changes; if overheated severely on one single occasion, or if brake pad material residues have transferred onto/into the surface of the disc. This can cause the steel or iron to transform partially (in spots) into something called martensite, which is way harder than the surrounding steel/iron. Once this has happened, it's nearly impossible to make the disc ever work properly even if you'd have it ground or blasted, as these changes go deep. The sensation will be a pulsating feeling, as these spots offer different coefficient of friction compared to the rest of the disc. This may be caused by improper bedding in of new pads, or incorrect pad material,and the solution is to replace the disc.

this would explain a lot, and plays to my inclination of finding some other discs to install.

I seriously doubt that any master cylinder, or any caliper can cause a pulsating feeling, no matter how badly bled they might be. If your discs are straight, consider the above alternative.

When I said a deeper problem than just a warped rotor, I was thinking more along the lines of slight damage to either the mounting surface of the wheel for the disc, or somehow the front axle/fork assembly doesn't align right in relationship with the wheel. although the bike was in one piece when I bought it, I have reason to believe it was crashed at one point in time, and that there MIGHT be something wrong there. I have not seen anything during many of the times the front has been apart, but it takes something like GMD Computrack to find these discrepancies. I am really hoping that this isn't the case and I will be looking into new rotors first. Thanks for your reply.

/Lasse
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Re: Jetting Guru's....

Post by L.Svedberg »

Just use a dial indicator to check both discs for warpage/throw. If none is measured, fine; get new discs, and if you find an unacceptable throw; remove the discs and measure the mounting surfaces to find the cause of the throw.

Bad brakes SUCK.

Good luck!

/Lasse

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