CB450 Shifting Issues

[stillatwork]

I have a CB450 that is having a hard time shifting. Recently changed the shifter shaft oil seal (replaced with new NOS). The bike isn't shifting from first to second gear or from neutral to second gear. I noticed there's a fair amount of side play in the shifter lever (in and out) can anyone tell me how far in or out the lever should be? When it's all the way in the bike shifts into first and neutral great but not second. Any ideas?

 

[frogman]

When you replaced the seal did you make sure the washer on that side was reinstalled as well as the cir-clip? Did the clip stay in place?

 

[stillatwork]

Yeah. I did notice from pulling the crankcase a few times to check my work that the circlip doesn't do the best job at holding the washer tight to the seal. It isn't a NOS One, just one I had in my garage that fit..so Maybe that's it? I just don't see how that would prevent the bike from shifting up and down though?

 

[Flugtechnik]

If the shift arm is allowed to move too far to the left or the right, the little "claw" part of the arm can come off of the shift drum and you won't be able to shift any more.
This is located under the clutch cover.

 

[cqyqte]

I found the same issue with the wandering c-clip and made a shouldered set screw cap to hold it in place...

 

[cqyqte]

The c-clip fits in the back groove and cannot expand which keeps it in the shiftshaft recess.

 

[stillatwork]

I think something is going on on the right side of the case. I'm going to get in the garage friday and this weekend and will keep you guys in the loop.

 

[stillatwork]

So I'm looking at Flogtechnik's second picture. It almost seems like my shifter arm isn't catching the wheel that moves the gears around that it is in. I notice that it isn't too much the alignment but the fact that maybe that arm is either A worn or B the spring on the bottom of it isn't strong enough to allow "snapping back". The bike shifts forcefully but only if I bring the shifter foot lever back up. It will not snap back on it's own. At times too, the shifter arm will not engage the wheel, it wll just extend out as it was shifting the wheel clockwise or cc then not work

 

[alzcbz]

I believe the self-centering action of the shifter happens from the spring at the lower part of the shift shaft. Make sure the shaft is centered around that pin.

 

[stillatwork]

So how often do you need to replace the entire shaft with the arm selector assembly? Would the spring be a better way to start?

 

[stillatwork]

So I'm going to replace the bottom main spring and get a NOS circlip and see what that does.how often does the entire gearshift spindle arm go? Has anyone had to replace it? Does anyone have one for sale? Any more advice on this issue? I can post a video tonight

 

[cqyqte]

The nature of the design for the shift shaft assembly allows for lateral forces of the riders foot against the shift pedal to be applied against the circlip on the shaft, so much so that the circlip is forced to expand and slip out of the shaft groove. This allows the shaft to move towards the rightside of the motor causing poor/improper alignment of the shifter and shift drum which sits behind the clutch basket. Movement to the right can be enough for the shifter to miss the drum completely. If you reposition the shift shaft and the leftside circlip and create a cap similar to the one I made the circlip will be maintained in it's groove and shifting issues should be resolved.

 

[stillatwork]

All: Here is a link to what's going on with the bike. I have a NOS 12MM Honda Circlip in there, and side play is minimized. Im thinking the entire gear shift spindle needs to be replaced since the arm that's welded onto it isn't engaging the wheel that cycles the gears. Any other ideas?

https://youtu.be/xm9y2Bp8QPI

 

[frogman]

Had to watch it twice to see it, nothing wrong with the shaft its doing what it can. If anything you are not pushing it FAR enough as it looked like it wasn't hitting the stop. That LARGE roller is NOT moving, its job is to index the individual gears and help force the drum to turn. I can't see if the spring that pushes it back into the drum is there or if it is lined up correctly with the slot it is supposed to be in.

Those rollers are known issues with 450s as the rivet that holds it onto the arm is softer than the roller itself and will wear to the point they do not do their job correctly. The star wheel behind that plate the other roller rides on will also wear down the tips of the stars and cause issues with solid shifting feel and the ability to stay in place.

At least that is what I saw and I have been there with mine. I need to find a new star for mine but replacing that roller really helped.

 

[stillatwork]

Thanks man. Where did you find your roller?

 

[frogman]

Ebay has them used occasionally, I drilled the rivet out on mine and replaced it with a bolt modified to fit.

 

[stillatwork]

Just to be clear you're talking about the roller to the left of the one that the arm physically touches right?

 

[xb33bsa]

yeah check the roller wheels its amazing how badly i have seen them worn on the 350 and 450
also check the spring and ball detent wait does the 450 have one ? well look at that of it does
i have quite a few 450 parts if you need any of that lashup pm you can have the stuff for shipping and a couple cups of coffee

 

[stillatwork]

awesome thanks a lot. I'm going to get into this in the next few days and ill get back to everyone.

 

[Flugtechnik]

It is hard to tell visually if the roller is bad, you need to take it off to see if there is free play.

Also, look for wear on the drum where that wheel rides.

I got some parts from a cb500t and they seem to have less wear. They are different part numbers, look the same functionally, but appear to be made differently. Maybe they solved the wear problem.