I give up. need help or advice.

[Jens]

Hi, like topic say iam lost here. dunno what to do. problem is

My bike is a VTR 1000F from 1997. SC36 stel number says JH2SC36A2VM001529

I bought a pair of Leo Vince exhaust.

When i put the exhaust on, the bike run fine, the db killer wass in. I took the DB killers out, and the problem started. it ran as i wass missing fuel, and the plugs wass white as hell.

I put a new main jet in, Front 180. rear 190. the needel is raised with 2 washers they are 0.60 each, pilot screw are front 2.5, rear 3.5.
The bike run fine with this setup. also at high speed (230+) i have a standard air filter in it.

The front plug are good nice color. brownís. the rear is grey/white. more white the gray it looks like. when i take the speed off the bike, its says a noise from the exhauset, like it farts. puf puf puf.

I tryed raise the pilot screw a bit more, and then the puf puf goes away, but then i have problem a high speed arround 190-200 when it have to work., its like it aint getting enouch fuel, or maybe to mouch ?

I have cleaned the carb, and re synced them, still the same. also new plugs in it.

any ideas or advice would save my day

Thx. Jens

[Phil-VTwin]

I feel your pain Jens, carbs can be a nightmare!

There is a good write-up on the Factory Pro website about tuning them, basically IGNORE everything else and get the main jetting right then worry about pilot jets and air screws.

From what you said about raising the needles I take it the carbs still have the original needles in?

Also the jets you fitted, where did these come from?

[tony.mon]

The noise from the exhaust on the over-run (off the throttle) is unburnt fuel burning in the exhaust system.
it can only do this if air (and fresh oxygen) is being allowed into the exhaust pipe, otherwise it flames as the unburnt but hot fuel meets fresh oxygen after it exits form the end of the exhaust.

So I'd say you have an air leak somewhere in the exhaust system, either at the downpipe/head joint, the exhaust connector joints or where the new cans join to the downpipes.

Now, if you still have the standard header pipes(downpipes) then these go 2:1:2, (so the two exhaust flows combine in the middle) so any change due to the new cans should affect both cylinders fairly equally.
As the front plug is fine, I'd guess that the new cans themselves aren't causing the problem.

So you'll need to investigate why the rear cylinder is running so lean compared to the front one.

Please be aware that not all jet sizes are equal.
Apparently a 190 (for example) from Dynojet isn't the same size as a Honda 190 jet.
So if you've mixed some jet kit (Dynojet or Factory Pro) jets with standard ones they may well not be following an expected pattern- so a Dynojet 190 might be smaller than a Honda 185, or which ever way round the discrepancy is- not sure.)

Can you check that the carbs are sitting properly in the inlet stubs, that there's no small crack in the stubs themselves, and that the vacuum take-offs are not leaking?
Any of those might give you an air bleed into the inlet side of just one cylinder, and might give the symptoms you describe.

Good luck- this'll be tricky to fault-find, I would think.

[Jens]

yep its a nightmare.

Bots jets are from a jet kit, so they arnt mixed up with honda´s.

I found out in my exhaust system underneth where all the pipes go together. in the buttom of it, there is a small hole. looks like its factory made. like if there are water in the pipes. so it can run out. maybe that could cause the problem ?

Any one have that also ?

jens.

[Stratman]

yep its a nightmare.

Bots jets are from a jet kit, so they arnt mixed up with honda´s.

I found out in my exhaust system underneth where all the pipes go together. in the buttom of it, there is a small hole. looks like its factory made. like if there are water in the pipes. so it can run out. maybe that could cause the problem ?

Any one have that also ?

jens.

No holes in mine

[tony.mon]

Don't know if that's standard, as I don't have standard pipes.

But try temporarily sealing up the hole and see if it stops your problem.

[Pete.L]

On the rear pot the header pipe is only about a foot long and then it joins the rest of the system. The join is hidden by the swing arm and it often blows the gasket out and leaks. Check the joint, I've just had it go on the SP too, now that's a pain to change

Pete.l