CRF450R Transmission Problem

[Indy]

I'll do my best to explain my problem.
2004 CRF450R

While out riding my gear shifter seemed to "loosen up". It then eventually quit shifting and was stuck in gear. The gear shift moved up and down but did not return to its neutral setting, it stayed where it was moved to.

I pulled the clutch cover off, pulled out the clutch, pulled the next cover and started inspecting the shifter.

The gearshift spindle goes through the motor and connects to the drum shifter. The cam on the shifter spindle goes inside the slot for the drum shifter. This cam came out of the drum shifter slot and caused my shifter to behave as it did.

I have consulted my owners manual and then discussed this situation with my dealers mechanics about why this would happen. According to the manual and the dealers exploded diagram all parts are in place. Mechanic was stumped.
I put it all back together and the same thing happened. :bang:

Have any ideas? If a better explanation is required than the above ramble let me know.

 

[Ol'89r]

Make sure the weld on the shifter spindle is not broken. Remove the shift shaft and clamp the spindle in a vice. Install the shift lever on the shaft and try to move the shaft within the spindle. I have seen the weld break on a couple of XR engines and it will allow the spindle to move away from the drum. The shaft can also rotate in the spindle. It is very hard to see when you visually inspect the weld so, you have to clamp it in a vice and put some pressure on it.

If the weld it broken, just have it tig welded.

 

[whenfoxforks-ruled]

What piece is doing what?http://houseofmotorcycles.bikebandit.com/parts/Honda/CRF450R/2004/1135648, did 18 come out of 9?

 

[Indy]

Correct 18 did come off 9. Any thoughts on why this would happen? Good link showing the parts.

 

[Ol'89r]

Make sure the weld on the shifter spindle is not broken. I have seen the weld break on a couple of XR engines and it will allow the spindle to move away from the drum. The shaft can also rotate in the spindle. It is very hard to see when you visually inspect the weld so, you have to clamp it in a vice and put some pressure on it.
QUOTE]

Check the weld where the flat arm on #18 is welded to the shift shaft itself. Also check that the flat arm on #18 is not bent. This will allow #18 to move away from #9.

 

[whenfoxforks-ruled]

#18 can also move outward under stress. Check the cover area,it stops it from going to far. #8 could be loose,but #14 holds #9 in place. And check the weld like Ol'89er said. This is really weird,but not as confusing! Make sure to locktite 8,21 and 27,and do not lose #10!

 

[Indy]

I finally had time to look into this. I inspected all the welds, applied torque to the shafts and they seem to be good, I started tightening all bolts and I found a loose bolt holding a gear, the one under the hex plug that can be unscrewed from the side of the case. I applied lock tight to the bolt and tightened it and reassembled the bike. No problems after one hour of riding around the house; hopefully I can test it more today.

The bolt is number 12:

http://houseofmotorcycles.bikebandit.com/parts/Honda/CRF450R/2004/1134086

I previously had the transmission gone through by a local shop and they had all this apart, I guess they forgot to tighten and/or lock-tight that bolt. All the other bolts, fasteners seemed tight when I was going through them. I’m not sure why the bolt and gear would affect the shifter?

Thanks for the replies/help. Indy.

 

[whenfoxforks-ruled]

How did the crankshaft drive gear effect shifting????? It does not figure,

 

[Indy]

It does not make any sense whatsoever. Coincidental at best.
Still shifting fine.
Could a direct hit to the shifter cause this? I was thinking a hit from a rock or my boots directly onto the shifter shaft might push the shifter out of #9.

 

[whenfoxforks-ruled]

Most definitely,the clutch cover has a cast stop that prevents this! Under the correct circumstances it jumps out of alignment,and back in,and it will not shift properly. The bolt you were about earlier has nothing to do with shifting,just a sloppy mechanic! I would assure him that he will no longer be taking my money for half assing my motor back together,and what else did he forget to torque?

 

[Indy]

I would assure him that he will no longer be taking my money for half assing my motor back together,and what else did he forget to torque?

The mechanic I sent my bike to has been doing our riding group's suspension for the last five years - and is great at it, always good service. Never had problem before this.

The shop recently relocated so it's not likely they will see my bike.

Hopefully everything else is good? I don't think that I will rip into it any deeper?