Since i have got my bike i have had nothing but trouble with the engine, spittin, sputterin and backfiring. I dont know if is a common problem but i will address it as if it was. I have messed with jets out the butt, but with no luck, untill i thought of a modification that was done on the 426. The BK mod change the engine's entire mood. It revs so quick with power that is usable and runs awesome. i am currently one up on the pilot jet and running a 170 main, needle is in stock position, and i also am running a DR. D pipe. There is a small problem with this mod on the 450 though, the hole must be drilled in the throttle cover between the bottom mounting tab and the drain hose, there is not much room there but i cleaned out a nice spot with a dremel tool which made room for my bolt. here is a website that explains the BK mod if you are not sure what it is. http://motoman393.thumpertalk.com/tech/carb.html I hope this helps someone out there. One more good tip i found is that during washing the bike water seems to find its way into every electrical connection on the bike..... solution, clean everything with contact cleaner and puchase a tube of dielectric grease and apply as needed. If there is any other tricks to this bike let me know i have been fixin everything. I got the clutch fixed with the 426 plate and shortened the engagement arm by 2mm and a hebo hydralic clutch to top it all off.


Dan
99'yz400f
03'yz450f

Got any pics?

What size was this bolt with the spring? or does a spring fit too?
I know what you mean about a small hole, (Real Small)

The 03250F carb's are the same. Some guys are having the same issues.
I have a P-38 and it works really well. No problems at all.
But heck, if people can get an adjustment screw to stop the cam where they
want it to like the older models from fully turning all the way,, Awesome!

Good job to you.
As stated before me>>> Pics?

PS. did you have to offset the hole alittle to the left side of the cover from center?
Thanks

i would post a pic but i am not sure how to. Sorry. i can email some pics if your interested.

Dan

I am interested Dan
and so are alot of people.

I looked at my cover again,
I'll be working on it soon too,I measured it before.and there was no room for mistake because it's so thin after you dremel what you need there to keep water and dirt out. (the inside edge of the cover I mean)

How much of that screw actually touches the cam lever?
Is it dead center of the lever? or alittle on the right of it barely?
Bolt size? Spring?

Thanks again Dan.

Send me a pic.  swiftT1@hotmail.com

 

I'm still waiting too. Jamener@aol.com

I'd like a pic too. mixel@bellsouth.net

When i drilled by hole it was at a slight angle to get more surface of the bolt on the cam, and i believe i have the whole bolt end on the cam. i used a 6-32 tap and a 1" bolt and washer and a spring that fit the bolt. Then after i got it set to where i wanted it i put some silocone on it to keep it in place, and to seal anything that my have been a problem around the threads.

Dan

Pics supplied by Dan.

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