shifting issues 2012 honda 450r

hey im just wondering if anyone has the same issue with there honda. i changed the oil several times and am running with moly it sometimes from 2nd to 3rd i think it seems to miss the shift and i get a terrible sound that sounds like its in between gears( like a grinding sound) i heard people say its your shift fork but i dont wanna change thatr and still have the same problem.

i have done the same thing on my crf250r. You need to make sure you get a good solid shift in and have your shifter in a comfortable position. If it continues i would dig into it but you need to make sure its not just you. If you have the tranny gears tumbled/polished it will shift way better.

the engagement dogs have rounded edges on your transmission gears.

This condition usually gets progressively worse until you replace the 2-3 gear sets and bushings.

ya i thought it was me and my shifting but it seems to only happen in between 2nd and 3rd, and is it that bad of a job to do.. replace the 2-3 gear sets

ya i thought it was me and my shifting but it seems to only happen in between 2nd and 3rd, and is it that bad of a job to do.. replace the 2-3 gear sets

 

Its an easy job. The only special tools you'll need is a flywheel puller. You'll be splitting the cases I'd replace the crank mains, and... shoot  I could go on and on....

Be sure to get both gears, and replace the shaft bushing on both shafts. it does'nt ad that much. 

Ok so I got it apart and part of the dog is worn or rounded so I thought that was the issue so I put a socket on the bolt and try switching the gears manually and it was still getting hung up in the gears. So I split the case and it looks like one of the forks on the bottem side has some rubbing marks. Could all this be cause of bent fork cause dogs where wore out ? I don't wanna replace these two parts and find out it doesn't fix it lol. Thanks

when the dogs round they act like ramps and thrust apart.

the story goes like this.

you pull the clutch

you click up on the shift lever the shift drum is rotated

the fork moves the gear and after it clears the dogs the drum finishes its rotation and the detent wheel/arm locks the shift drum in positon.

after the drum is locked

you release the clutch

you open the throttle

the round or chipped dogs act like ramps and the gears push apart

the shift fork being in a groove perpendicular to the shift drums axis of rotation cant turn the movement into rotation of the shift drum it has no where to go no way to get out of the way it just smacks the shift fork and lays it over.

 

If your shift fork has any ugly wear, its came from the gear being thrust into it by the screwed up dogs and is probably bent and needs to be replaced.

if the shift fork was banged, and bent, and thrust into the shift drum there can be a chink in the shift drum on that forks track. if this is the case you need a new shift drum.

 

after the first time it jumps out of gear it just gets worse now the ramps are there and theres a ton of clearance since that shift fork never pushes the gear as far as it use to and just lends itself to popping out of gear.

 

i have some first hand experience because my 09 destroyed 5th, a shift fork, the shift drum, and the shift fork shaft.  I ended up moving 5th gear over with some machine work and a spacer so it engages farther.

 

my 3rd gear was fine so i didn't really look at what could be done to help third.

also is recommended to use the stiffer crf450x detente spring a hole 3.00$ part just heavier wire it can be bent for some extra preload too.

 

when you relpace your gears you need to replace all the bushings they ride on as well.

and any worn shift fork,

also for 30$ you can have a new shift drum.

this happens on these bikes somewhat randomly and i suspect it has to do with tolerances, of everything but maybe a big one is the shift drum.

Out of curiosity, what kind of trans oil are you running?

engleracing... what an awesome post just what i was looking for on how everything works im going to the shop this week and run through what you typed out mechanically (its how i learn best hands on lol) thanks for the post and on what i should need to get my bike ready for the upcoming season!!

 

Shawn_mc i am running the honda engine oil without moly ( i think unless i got it mixed up its bin a while since i changed the oil) but its the honda oil

Out of curiosity, what kind of trans oil are you running?

 

when the dogs round they act like ramps and thrust apart.

the story goes like this.

you pull the clutch

you click up on the shift lever the shift drum is rotated

the fork moves the gear and after it clears the dogs the drum finishes its rotation and the detent wheel/arm locks the shift drum in positon.

after the drum is locked

you release the clutch

you open the throttle

the round or chipped dogs act like ramps and the gears push apart

the shift fork being in a groove perpendicular to the shift drums axis of rotation cant turn the movement into rotation of the shift drum it has no where to go no way to get out of the way it just smacks the shift fork and lays it over.

 

If your shift fork has any ugly wear, its came from the gear being thrust into it by the screwed up dogs and is probably bent and needs to be replaced.

if the shift fork was banged, and bent, and thrust into the shift drum there can be a chink in the shift drum on that forks track. if this is the case you need a new shift drum.

 

after the first time it jumps out of gear it just gets worse now the ramps are there and theres a ton of clearance since that shift fork never pushes the gear as far as it use to and just lends itself to popping out of gear.

 

i have some first hand experience because my 09 destroyed 5th, a shift fork, the shift drum, and the shift fork shaft.  I ended up moving 5th gear over with some machine work and a spacer so it engages farther.

 

my 3rd gear was fine so i didn't really look at what could be done to help third.

also is recommended to use the stiffer crf450x detente spring a hole 3.00$ part just heavier wire it can be bent for some extra preload too.

 

when you relpace your gears you need to replace all the bushings they ride on as well.

and any worn shift fork,

also for 30$ you can have a new shift drum.

this happens on these bikes somewhat randomly and i suspect it has to do with tolerances, of everything but maybe a big one is the shift drum.

 

engleracing... what an awesome post just what i was looking for on how everything works im going to the shop this week and run through what you typed out mechanically (its how i learn best hands on lol) thanks for the post and on what i should need to get my bike ready for the upcoming season!!

 

Shawn_mc i am running the honda engine oil without moly ( i think unless i got it mixed up its bin a while since i changed the oil) but its the honda oil

 

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