Anyone ever had this issue?

Budget_Blaster

New Member
Dec 25, 2009
1,630
13
0
Illinois
I went ahead and rebuilt this new blasters bottom end new bearings seals the whole 9...

I get it together and find that i can only shift to 3rd before it bound and got too tight to turn the output shaft sooooo i had to disassemble thinking i missed something and did this 3 times and each time found nothing wrong.

Finally i noticed a couple of metal chips on the bench and right under the shift drum.Come to find out the shift star was able to move 3/4 of a complete circle and caused the binding.Luckily i had one on the shelf that had the shift star welded to the drum slapped it in reassembled and smooth as silk now.

I got to looking at the old drum it seems that woodruff keyway was all broken and split and thats where the metal chips were from i found.

Ill post pics of it ive never seen it happen but i did find i had a bent shifter rod and also swapped that out think it make be an indication to what happened to the shift drum?
 
i had a shift star go bad once ???, it'd jump out of gear when leaving off the throttle
not sure what the malfunction was, i was told shift star
it was before i worked on these, and just had someone else fix it

but good find on your part
 
i had a shift star go bad once ???, it'd jump out of gear when leaving off the throttle
not sure what the malfunction was, i was told shift star
it was before i worked on these, and just had someone else fix it

but good find on your part


Well heres what i found....


311017_10150890568600328_540740327_21324307_1436616877_n.jpg


300542_10150890568715328_540740327_21324310_1170027905_n.jpg


376491_10150890572690328_540740327_21324327_327568120_n.jpg


Heres the remedy...

391177_10150890572820328_540740327_21324328_1819360109_n.jpg


Feels very positive and crisp and clean shifting on the bench.
 
I've seen many of them chipped like that at the key. It's caused by the retaining screw backing off or not being torqued and locked during assembly. Who knows.......it could be a bad design by Yamaha. Maybe that's why they started welding them.
 
So I opened up my clutch cover and removed the clutch basket and this is what I found.. See pics. Shift star on the left was in the quad and the one on the right is a spare I have. Can the better shift star we welded or should i just split the case and inspect the transmission for any other damage? thoughts?
 

Attachments

  • 20180501_194736.jpg
    20180501_194736.jpg
    1.5 MB · Views: 136
  • 20180501_193642.jpg
    20180501_193642.jpg
    2.8 MB · Views: 114
Star on left is modified, actually shifts easier/better.
Might be better to get different shaft and new key. Not saying it wouldn't work, but would be major PIA if/when you have to split cases
 
I will have to split the case the change the shift drum.. unless i weld the shift star to the end of the shaft. I am leaning on splitting the case so i can inspect everything on the transmission side.