Help please with tuning my bike

Ok test rode it again today and still having the same issues. I replaced the intake boot as the stock one had a suspect crack that goes half way through, but still no change in idle with the carb cleaner test with either boot. I also replaced the seal that is on the slide in the carb just because, the stock one seemed ok but new one seems better. Put in a new 45 pilot as the older one was a bit plugged. None of these changes made any difference. I have played with the jetting from pilots to needles to clip positions to mains richer and leaner. Gets worse if I go leaner but even going way rich doesn't help.

I am convinced there is no air leak and that it also isn't a jetting issue. I'm thinking electrical? Like timing or the TPS possibly? I bench tested the TPS and could not get a reading on it no matter the throttle position. That tells me it's bad I would guess. I ran the bike with it unplugged and it ran the same way.

I've also read that others have unplugged it and their bikes still run as good as plugged in.

SO WHAT THE HECK IS WRONG HERE?

There is no more cruising on my bike, anything over 1/8th throttle is hauling A**!

crack in the carb slide, maybe? Slide put in backwards?

I made sure it was in the right way, no cracks visible at least.

Are you sure the slide linkage and pulley is all put together right? Doesn't sound like jetting or electrical...how about the hot start...stuck open?

Yeah the slide and linkage is all working proper. The hot start is good, I checked it a couple times including when I had the top cap off the carb, you can see the hot start plunger go in and out when you look in there. The bike runs somewhat like when you have the hot start out, only a little worse.

"Bike has Hotcam auto decomp exhaust cam,FMF powerbomb and FMF Q4 (newer version custom fit from a 450).

Test rode the bike today, it is FAST but almost too fast and out of control. "

Was the cam and exhaust on before this started, or did this start once you added the cam and exhaust?

If this only started after adding the cam and exhaust, I think I know exactly what the "problem" is...

No as I mentioned I have checked cam timing and valve clearances several times, triple checking them. There is nothing wrong with the hotcam, others run it with no issues. Why would mine be different? The exhaust is just exhaust, no leaks no issues.

While the problem did start after I put all this stuff on including new piston/ rings/ gaskets and such, it did run fine for a while before this problem occured.

OK i just know borrowed my friends multimeter (better than mine) and got a good reading on the TPS. It reads 4.97k Ohms both closed and fully open throttle. That falls in the spec range for full throttle but not closed. So that tells me it's bad as it reads fully open all the time. Ok that's a problem sure.

But why do some people have no issues when they unplug or go bad?

OK i just know borrowed my friends multimeter (better than mine) and got a good reading on the TPS. It reads 4.97k Ohms both closed and fully open throttle. That falls in the spec range for full throttle but not closed. So that tells me it's bad as it reads fully open all the time. Ok that's a problem sure.

But why do some people have no issues when they unplug or go bad?

Here is a problem with your claims, the answer to the problem is probably what is wrong with your bike.

At 1/4 throttle, under load, your bike does not go that fast. In top gear, on a hill, it will only do about 35. Far from taking off. At 1/4 throttle, you only are allowing the engine 1/4 of the total potential air. If you add too much fuel, the bike will run even worse. So we have a max speed under load. On a flat road with not resistance other than air, yes, eventually, the bike will go fast, possibly as fast as 70. But not under load.

Therefore, based on your claims, you must be getting more air and more fuel (Too little fuel would also put a 'wrench in the mix'). Somehow, your bike is dumping extra fuel and air. Assuming your float needle seat works properly, the only way to get extra fuel is via the choke. The slide could be moving on the throttle shaft or the throttle shaft moving inside of the throttle wheel.

An electrical issue would only make the bike slower.

Sounds to me more like the timing chain has jumped a tooth.

I asked that because after I added hot cams, and a FMF PowerCore to my 450 my description of my bike became:

"Explosive" and "too much, to soon - lights up way to quick, and way to hard"

lol

Your description of yours as "There is no more cruising on my bike, anything over 1/8th throttle is hauling A**!" pretty much summed it up actually.....

But if your issue started AFTER the mods, and not as soon as you did the mods, then, yes, you got something else going on.

Here is a problem with your claims, the answer to the problem is probably what is wrong with your bike.

At 1/4 throttle, under load, your bike does not go that fast. In top gear, on a hill, it will only do about 35. Far from taking off. At 1/4 throttle, you only are allowing the engine 1/4 of the total potential air. If you add too much fuel, the bike will run even worse. So we have a max speed under load. On a flat road with not resistance other than air, yes, eventually, the bike will go fast, possibly as fast as 70. But not under load.

Therefore, based on your claims, you must be getting more air and more fuel (Too little fuel would also put a 'wrench in the mix'). Somehow, your bike is dumping extra fuel and air. Assuming your float needle seat works properly, the only way to get extra fuel is via the choke. The slide could be moving on the throttle shaft or the throttle shaft moving inside of the throttle wheel.

An electrical issue would only make the bike slower.

Well I will check again but I did not see anything wrong with choke. It does run differently with the choke on, runs a little worse like it's missing. I also did not see anything wrong witht the slide or throttle wheel.

I understand what you are saying but I don't know how getting more air and fuel will make my bike run like it's lean and vibrate alot. That's the feeling I get anyway. But it's just too much power too soon, and it's not smooth power, it comes on strong and vibrates the whole bike. You should be able to put around and 1/8th to 1/4 throttle.

Re-read the procedure for checking the TPS (I did mine wrong the first time as well) as I think you were on the wrong pins. Even if your TPS was bad I doubt this is the problem as it's more of a "fine tune" item as far as overall running goes.

People here are trying to help so don't get too defensive. It really seemed like to me that it's just a power thing that changed after the rebuild. You'd be VERY surprised as to how much the WR wakes up after the free mods and how much an exhaust and a cam can change a powerband. But if it was fine for a while (not just warming up on the stand or a test run up the street) I'd start with the throttle cable at the grip and work down checking for mechanical issues.

Had a buddy who's throttle cable slipped off the grip and the bike acted weird until I got on and said the throttle pulled hard. Sometimes it's the simple things that get overlooked, especially after mods.

Mike

New Update:

I just tested the pickup coil, cdi and ignition coil. Pickup and cdi test within spec, not so much on the ignition coil. While testing the primary coil resistance it came in right at the high end of spec. But the secondary coil resistance does not give a consistant reading and sometimes not at all. So I figure there is a short of some sort between the coil and the end of the plug wire.

A new coil should fix my problem I hope. I will borrow my friends good coil off his bike and test it on mine before I buy one.

Any thoughts?

Have you ever looked at the clutch on this bike? You have had this bike awhile right? So you know how fast it goes?

Oh yeah I've had the bike since new and have done all the work myself. It has been a great bike until this started. I have not yet looked at the clutch but was sort of thinking that the vibration may have something to do with it. Possibly

New Update:

I just tested the pickup coil, cdi and ignition coil. Pickup and cdi test within spec, not so much on the ignition coil. While testing the primary coil resistance it came in right at the high end of spec. But the secondary coil resistance does not give a consistant reading and sometimes not at all. So I figure there is a short of some sort between the coil and the end of the plug wire.

A new coil should fix my problem I hope. I will borrow my friends good coil off his bike and test it on mine before I buy one.

Any thoughts?

Coil could cause a miss that might appear as vibration...but not sure about the narrow powerband aspect of your problem...let us know how the coil swap goes...If that's the problem, you may want to go the "coil on cap" route that the 450 uses (an R1 or R6 unit works, too, and you can get the connector from MotorCraft if the coil doesn't come with one) to clean up the installation a bit...

Alright finally some prgress! I borrowed my friends' coil and bolted it up. Bike started up quickly and seems much better on the stand so far. Hard starting went away, no more having to give it throttle. Vibration is down and powerband is much smoother and more back to normal. Now I will have to test ride to make sure.

Yeah Birdy I have read about the Hayabusa/ R1/ R6 coils and I am going to end up getting some of those. They are cheaper than buying a new OE one. Of course they are used on ebay, but if I buy a set of 4 with the wire harness I'm sure I'll manage to have at least one good one for a long while.

Checked out the clutch all is good and well within spec on every plate. Nothing worn or broken. I was thinking maybe something in there was causing vibration but no.

Put on a R6 coil today it runs better (on the stand) than mine but seems the same as my friends coil I tried.

With the seat off I could hear a clicking sound like the slide possibly moving around at a slight throttle opening probably 1/8th throttle. Hmmm is this normal? Probably not huh?

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