Blaze45

I dont even know where to start. I guess I can just describe the symptoms and see what people think.

It has been a money pit since day one. And highly discouraging.

Replaced the reeds because they were cracked. Leaned the bike out via air screw and stopped bogging.

Summer came around and adjusted the need clip to the leanest postion and re jetted to get rid of bog that still existed with warmer weather.

Currently on a 370 MJ and 30 pilot. (recommend via Honda OEM manual is 360 MJ and 27.5 PJ) The needle is some screwy # that isn't even on the jetting chart. Took the bike to the dunes and the power band continually got smaller and smaller. I couldn't climb hills that the 01 YZ 250 could make it up without an issue.

Bike is geared quite low with a 12 tooth sprocket up front. Everyone I am with tells me that if I switch out the sprocket it will make all the difference because I will get more wheel speed and be able to turn the paddle faster = better at the dunes.

The bike exhibited symptoms of bad crank seal on a trail ride recently (weird smelling exhaust and disappearing trans fluid) so I replaced that and did a top end. When I did the top end, there really wasn't any glazing that I could tell. No scaring. The exhaust bridge on the piston had some wear but nothing serious.

With the new Wiseco piston it stil knocks, more then it did with the old piston at the dunes which scares me. Stock Honda OEM base gasket. 91 Octane ethanol free maxima 35:1. No spooge.

When I took the clutch housing cover off to do the crank seal, I discovered that I need a new clutch basket and mostly likely inner hub and while I am at it, clutch. How would these worn parts influence power on the bike?

That dumb 01 YZ can wheelie up the dunes, and mine cannot. I have to drop the clutch at full throttle to get the bike to even move. I dropped the clutch and whacked the throttle on that on the YZ and almost looped out when I was taking off!!!!

It didn't help that I put a 10 paddle sand tie on the bike after all this. Bogged the bike down a ton.

Plug is black.

I am really quite discouraged. : /

The 450s all seem to run great without an issue and climb hills I cant't. I want to stay 2 stroke, but the bike just isn't getting the job done and it seriously kills me.

Things to buy:

proper needle size and PJ size (recommended is a 27.5 PJ which nobody has)
clutch basket, inner hub and clutch

or

A new bike. That is seriously to the point I am at.

Any help is appreciated.

Orangegsx

These are great bikes. I wish there was a way I could take it for a spin and get a feel for the problem. It's hard to explain and interpret problems through the internet. I would try the needle jet and see how it goes. Also I'm assuming you know how to clean the power valve? If the clutch is not slipping I wouldn't spend money on replacing it until you track down this problem. I'm assuming it just has some grooves worn into the basket fingers? You can file these out to an extent. I usually only do it once or twice before just biting the bullet and replacing.

GraphiteAcc0rd

The '03 carb was junk...the '02 was MUCH better.

It really sounds like that motor is tired. Why 35:1? have you tried changing oils, and going to less oil, more fuel? What other jets have you tried?

With the black plug, you sound super rich. How bad is the air filter? Are you cleaning it after every ride?

Glenn743

The clutch has nothing to do with power. If the clutch basket is badly notched i would replace it. But thats not the problem. The plug being black is a red flag. How worn the piston is could be a problem. Compression check. The power valve not operating correctly by being dirty and gummed up could easily be the whole issue. Air filter maintainance is THE most important issue with a dirtbike. Just a start of things to check but i suspect the exhaust power valve.