Topic: FendersRule's getting his 'chit together with the help of Bill Lane

[fendersrule]

Well, as most of you know my CB450K5 restoration came to a complete halt by a transmission issue. It only took 20 miles for my transmission to start slipping first gear. My father did a great job in replacing the "obvious" things, but it turned out there was an issue that wasn't so obvious: a bent shifter paw. Shifter paws can be real #$%*s that eat everything up in its path.

I shipped all of my transmission parts to Bill. I had already known the obvious: The first gear fork was chewed up (was in great shape when installed). Interestingly enough, the original fork was chewed up in the same manner. This tells me that shifter forks seem to be an "effect" and not so much a "cause." Obviously, the "star wheel" was worn, but in my opinion it wasn't so bad to have caused issues (Bill may agree). Bill ultimately found a bent shifter paw. Now listen as this makes complete sense: If the shifter paw was bent, then it's NOT going to move the shift drum enough. That means the dogs and forks only "halfway" engage. Believe me: this will destroy your transmission. Bent shifter paws are not so obvious, either. You can't just "eye ball" them. Bill suggests removing the spring and spinning it around the rivet. If it makes contact with the arm, then it's bent. A tale-tale sign is to also look for wear around the teeth. My shifter paw was shifting some metal wear on one side which is another sign.

The only way I think a shifter paw can be bent is by abuse by the previous owner. Stomping on the shifter to get it to shift.

Lesson for everyone: If you are having transmission problems, don't just inspect/replace the obvious. Go over absolutely EVERYTHING. That is what my father didn't do. Posting on a forum complaining about shifting issues will get obvious responses. Don't just listen to what people say. Inspect absolutely EVERYTHING.

OK, enough soapboxing.

Parts back from Bill:



It's never a bad idea to shield #$%* from falling into your engine:


Fist step is to apply some oil to the shift drum and insert it:


Install the shift drum while sliding in the forks in the CORRECT orientation:


Align the shift drum so that the "notch" on the left side is facing upward if your engine is upside down. Install the fork pins so that they pass through into the drum labyrinth. They should just drop right in, long side first. Install the fork clips and make SURE that they are in the right orientation. Once that's done, I like to take needle nose pliers and "pull" up on the pins to assure that they are installed correctly:




Lay in the sprocket shaft in first while jiggling the L and R fork. Then install the other shaft:

[fendersrule]

When the shafts are installed, rotate the ends of the bearing caps so that the pins go into the holes. This is damned important. I've heard stories of people forgetting this step. Honestly, I'm not a mechanic, but I think if you "miss" this step then you shouldn't be working on engines in the first place. Here is what both shafts look like when they are properly seated into place:

[fendersrule]

Now is a good time to screw in the shift drum "stop bracket" that holds it into place behind the tensioners. I didn't take any pictures. Basically, I used blue thread lock and screwed the two screws in and got them as tight as I could with my hand. Also, the center screw that goes in the shift drum is already breathed with red thread lock: a very important step. THANKS BILL.

Now it's time to hook up the tensioners. I didn't take step-by-step pictures here because it's a slight #$%* and required two hands almost all the time.

Slip on the washer (easy to forget) and then slide on the large detent roller. Pay attention to which way the detent roller is facing:


Next, slide in the detent roller spacer so that it seats INSIDE of the large detent roller. Slide in the "skinnier" spring and force/wiggle/do whatever to get it into place over the large detent roller. Doing so is likely going to cause the spacer to come off from the detent roller. Here's a trick: grab the nut and then screw it into the spacer and then wiggle the detent roller so that it reinserts. This is an easy way to get the spacer re-seated.

Finally, slip on the larger spring along with the neutral detent roller (smaller one), force/wiggle/do whatever to get it into place, and then install the washer and the nut again. You may have to still wiggle stuff to get it to seat correctly. Hard to show all of this by pictures, but there's really only one way all of this works so just figure it out.

Now, you CANNOT FULLY test the shifting by just using the screw on the drum. To FULLY test the shifting you need the shifter paw. I haven't received my replacement yet. But, at this point, use the screw on the drum to test shifting into all gears while spinning one of the shafts in the appropriate direction. All of my work great. Some of the below pictures are dark, but the FSM shows a great picture to confirm each position.

First:



Neutral:



Second:



Third:



Fourth:



Fifth:

[Bill/BentON Racing]

Looking good. I ended up having to get star wheel and all other pieces that attach to drum. PO had abused the hell out of them, 2,000 miles looked like 200,000! Waiting on some shift drum guide clips now! Good info and pics, Bill

[fendersrule]

Thanks for the reply. I'm waiting for a shifter spindle. Can't find one.

You don't have a spare do yah?

[fendersrule]

Here are pictures showing what a bent spindle looks like. I had a machinist reset the rivet and do some straightening of the arm with a hydraulic press. These parts are very very hard to straighten because all of that work we did on the spindle didn't help much. What sucks even more is that you cannot "see" that it's bent. But here's a clear indicator; notice how the paw is touching the star wheel when installed:




I believe that the paw was the cause of my transmission failure.

Here's a spare paw that I have that's straight, but the spines are trashed so I can't use it. I installed it anyways for pictures to show the difference:

[Bill/BentON Racing]

Damn, too bad about the splines. I'll check around, Bill

[fendersrule]

Let me know if you need more tranny parts. I just ordered yet another spare transmission (will be my third spare).

[fendersrule]

Well, I think scored on the spindle that I got in. Needs an acid bath, but man, look how centered it sits over the star wheel. This is probably how it's supposed to look, huh?

[fendersrule]

Well, bad news. I soaked this in vinegar for two days, and it revealed three problems. 1) Corrosion on the rod. 2) crack on the knuckle, and 3) Bend on one of the knuckles.





None of those things really affect the perfect fitment that it has, but they are problems....

I have a plan...

[fendersrule]

Dropped this spindle and my original spindle down at a local machine shop. I had the good shaft transplanted, the crack welded, and the knuckle straightened.

Have not done a test fit yet. But they look like they did some excellent precision work.






They had that back to me in less than 24 hours.