What causes a MX bike to shift horribley

i have a 06 crf250r that does not want to shift. it goes into the first 2 gears fine but after that it is a real whore to shift. it gets real bad when you are on the gas hard, if you get on the gas hard it will not shift AT ALL. it takes about 5 seconds before it will even think about shifting. i am having the biggest problem with 3rd get but all the other areent that good either.

i have tried 3 different tanns oils at the exact oil recomendation. and they all suck so it is deffinatly the clutch. i want to get this fixed fast so i can start practesing i really need help:cry: :thumbsup::ride:

your clutch should'nt be the problem

most bikes are designed for clutchless shifts

check and see if your shift forks are bent

Not sure about the CRF250, but I do know for sure that my '06 CRF450R's transmission acts quirky if the trans. oil level is at Honda's recommended level. It needs more fluid for it to act properly. A lot of 450 owners run their trans. oil at a full quart, rather than the recommended 710 ml. Not that this is definitely your specific problem, but something you may want to check into.

your clutch should'nt be the problem

most bikes are designed for clutchless shifts

check and see if your shift forks are bent

+1 on the shift forks in the tranny

Assumption I made: You've changed your oil and checked the shift lever

Not sure about the CRF250, but I do know for sure that my '06 CRF450R's transmission acts quirky if the trans. oil level is at Honda's recommended level. It needs more fluid for it to act properly. A lot of 450 owners run their trans. oil at a full quart, rather than the recommended 710 ml. Not that this is definitely your specific problem, but something you may want to check into.

you do have a good point, my last oil change i put way to much oil in (on accident) the tranns and it seemed to shift way better.

but i am sure the 450 tranney holds more so i probaly shouldent a full quart in right......:thumbsup:

i agree with checking the shift fork...also i have found in my 06 rmz250 that full synthetic oil makes a HUGE difference in how well the bike shifts...i no you said you tried 3 dif oils but i use the maxima full synthetic and like it alot good luck:thumbsup:

your clutch should'nt be the problem

most bikes are designed for clutchless shifts

check and see if your shift forks are bent

as much as i hate to ask it but what are shift forks

another thing i would like to add...

i got a new tire on er today. i was hooking up big time so mabey that was causeing more that normal strain on the tranney copared to the slick with some bumps i had on recently. i noticed it shifted really bad right when the new tire got on too, but i also swich oils to from HP tannney oil to rotella that could have been contributing too.

but the tire should have nothing to do with it, its not like dirt bikes were make to run bald tires.

as much as i hate to ask it but what are shift forks

The internal part that makes the transmission do what your left foot is telling it t do.

I wouldn't go with a full quart in your transmission. Try about 10% additional to the recommended level and work from there. 10% overfill makes a night and day difference in my 450.

The internal part that makes the transmission do what your left foot is telling it t do.

I wouldn't go with a full quart in your transmission. Try about 10% additional to the recommended level and work from there. 10% overfill makes a night and day difference in my 450.

so does that require some tearing down:excuseme:

See the U shaped things above my rubber mallet?

281_8137.jpg

Those are shift forks, they are what physically move the gears on the input and output shafts which cause your transmission to shift.

so does that require some tearing down:excuseme:

It requires you to split the cases, and inspect your transmission.

so does that require some tearing down:excuseme:

Yes. Parts # 1, 2 & 3. (the diagram is for an '05, but shouldn't be many-if any differences)

http://oem.thumpertalk.com/2005CRF250gearshiftdrum.aspx

Try the easy and inexpensive options first and work towards the most difficult and expensive ones. Hopefully, you'll get lucky and it will be something simple...

so does that require some tearing down:excuseme:

Yep, case splittin. :thumbsup:

And, try going up about 50cc on oil at first, then 20cc, then 20cc. I prolly wouldn't go any more than that...but if 50cc helps, ya just gotta try and see. I believe going from the HP to the Rotella may have added some notchiness...but I'm not there, and it's hard to say.

Good luck!

BTW, this is a common symptom of a tranny that has been power-shifted under hard acceleration. If the clutch is not predominantly used, a momentary back off on the throttle will allow for less shift lever pressure required to move the shift levers...hence your problem IMHO.

What is the rating of the Rotella you put in the transmission? (i.e. 10W-30, 10W-40, etc.)

It requires you to split the cases, and inspect your transmission.

:thumbsup::ride::rant: that would really be pushing the mechanic skill to the absolute limit:cry:

but how do thoes shifter forks get bent in the first place

What is the rating of the Rotella you put in the transmission? (i.e. 10W-30, 10W-40, etc.)

the first oil i use was the honda HP oil, the second Rotella 15w-40 the third honda HP4 engine oil.

the HP when overfilled worked the best

:thumbsup::ride::rant: that would really be pushing the mechanic skill to the absolute limit:cry:

but how do thoes shifter forks get bent in the first place

some where a bad combo of not enough oil, too much traction and high stress on the gears such as full throttle shifting went into play and you got the short end of a bad deal

but how do thoes shifter forks get bent in the first place

One of two things....Tranny abuse(aka forced shifting under power) or metal fatigue(too many cycles).

well i have never really abused my clutch, (but mabey the guy before i owned it did) and to let you all know when i go to shift i am absolutley boddoming out the clutch lever on the handle bars, i is just does and go

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