426 wont shift


13 replies to this topic
  • cycometto

Posted August 03, 2010 - 05:39 AM

#1

ok soooo I need a little help, heres the run down.
started bike up let warm up a bit got on dropped into 1st and bike died with clutch fully pulled in. put back in nuetral started up again and clunked into first but didnt die this time. rode around shifting in and out of gears just fine. then parked. got back on a little later fired up and would not go into any gear and throttle would just rev the engine yet the bike would crawl foward on its own even with clutch fully pulled in?!?!

well I pulled the clutch basket off and dont know exactly what to look for as sign of failure. a few things i tought were odd was one spring on the clutch basket had far more torque than any of the others. Also not sure of the name but the outer clutch hub or basket on the back were that very large gear is with the springs laid into the housing, all of those springs are loose, loose like i can spin them with my fingers, is this normal? what else should i look for? Manual dosent really show how to test engament of clutch or maybe i missed it?

  • cycometto

Posted August 06, 2010 - 05:14 AM

#2

well upon futher inspection my clutch boss had some nice groves in it. I took the time to smooth all those out along side with the outer hub as well. and after a battle with trying to remove the broken fine cheese bolt they use for the clutch pressure plate I got it all back togeather. I have not fired it up and rode it around due to the fact that somthing is still really wrong. What I mean by that is with the bike sitting I can simply grab the shifter and click it through all the gears?!?!?! What could be the cuase of this?
Now when I pull the clutch lever in I can see the friction disk/plates being pushed apart so that means that portion is working right? Really could you some help here, kinda at a loss.

  • cycometto

Posted August 07, 2010 - 05:06 PM

#3

I NEED HELP!!!!!! lol

really I do tho. I think somthing is my transmission let go. If I put the bike in gear 1st or any other I can spin the back tire with my hand!!!!! I can do this even with the clutch pulled out. all the gears behined the outer hub still look great no signs of wear.


PLEASE HELP ME!:banana:

  • grayracer513

Posted August 07, 2010 - 08:27 PM

#4

You have the clutch removed?

  • cycometto

Posted August 08, 2010 - 08:21 AM

#5

yes sir, if the clutch assembly is in or out the results are the same. I can simply click through all the gears and roll the bike around as if it is nuetral the entire time.

  • grayracer513

Posted August 08, 2010 - 09:14 AM

#6

That's normal. It is the clutch that connects the engine to the transmission.

  • cycometto

Posted August 08, 2010 - 09:44 AM

#7

well I put new clutch plates in and rode the bike and all it did was act as if the clutch was semi engaged. I could rev up the engine in gear and let the clutch out the the bike would barely roll.

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  • grayracer513

Posted August 08, 2010 - 09:51 AM

#8

How much free travel was there in your clutch cable?

  • cycometto

Posted August 08, 2010 - 10:36 AM

#9

I tried it with all the slack out of the cable and also with the recommened 4mm of free play, same results......

  • grayracer513

Posted August 08, 2010 - 11:46 AM

#10

Take a good look at your clutch boss. If it has a steel insert in the center, it may have spun free of the casting.

Otherwise, assemble the clutch, leave the cover off, then put the bike in gear and see if you can force it to slip by pushing it. Maybe you can see what's actually going on. You may simply need a new clutch.

  • cycometto

Posted August 09, 2010 - 11:04 AM

#11

I will do this today and get back to you. Thanks for the input.

  • cycometto

Posted August 09, 2010 - 04:55 PM

#12

Ok so I think I found the culprit. Seams my outer clutch basket with the primary driven gear on the back has free play from left to right. I cant spin it a full revolution by hand, only a few degrees in rotation while holding the clutch basket and grabbing the gear and moving it. but I think installed with the rpms of the engine has plenty of power to rotate that gear and spin it free on the basket. Somthing else that asures me that this is going on is there are groving marks on the inside side cover from the clutch basket. Ill try to post some pics in a few here.

  • grayracer513

Posted August 09, 2010 - 04:56 PM

#13

That isn't good, but that isn't making it slip.

  • cycometto

Posted August 09, 2010 - 05:40 PM

#14

That isn't good, but that isn't making it slip.


Haha you are so right man, you saying that just changed how i was looking at this entire thing. while yes the primary gear dose have play and needs to be changed what was really cuasing all this mess was a stupid busted splines on the front sprocket. I spun the trasmission by hand and watched the front sprocket nut just spin and spin yet the teeth went no wear. took the sprocket off and sure nuff all busted off, was only held on by the nut. looks like just my sprocket and not the transmission shaft thank god.





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