Topic: Yet more CB 175 transmission woes.. #breakthrough#

[fmctm1sw]

So here's where I'm at with this.  Using the parts transmission I got off eBay (and really, I only used the "L" shift fork), I was able to procede.  I feel pretty good about what I've learned from observing my transmission sitting on the floor, not as complicated as I though but I still have to get the shift shaft and all that back in.  3rd gear just doesn't seem to be engaging the entire way to me.  The shift fork is obviously not new but I don't think it's worn to the point that it's not usable.  

Here's what I'm thinking.  If I could just get that gear that's circled to move over to the right ever so slightly, I'd feel a lot better about putting this back together.  the gear right next to it (what I figure to be 4th gear engages completely.  So completely actually the dogs on the gear barely clear when I move the shift drum around.  Lot of room there to play with.  Perhaps I could move the pair to the right somehow?  

I do remember the guy I talked to when I thought about selling it mentioning shimming it right when I put it back together.  Any thoughts or guidance appreciated...

[fmctm1sw]

Well.... I did it.  I was able to shift the shims around and move those gears a little.  It engages way better now.  This is after I could not find a NOS "L" shift fork.  I know it isn't the way Mr. Honda engineered it but considering the relative ease in getting this motor in and out I figured it was worth a shot.  I'll post back after I get it on the road.  Got 3 Bond 1194 on the way to seal the case....

[bryanj]

Is there a chance it ahs been apart previous and the shims mixed up?

[fmctm1sw]

Is there a chance it has been apart previous and the shims mixed up?

Possibly but I doubt it.  I know the engine has been split before (or at least and attempt was made) evidenced by the broken engine case bolts.  The transmission I got off eBay lines up the same way and the shims are in the same positions.  I tried the other shift drum as well, same thing...

[bryanj]

It would seem that either both are worn the same or thats the way its supposed to be. Its been more years than i care to talk about since i split the bottom of a 175 and even then i dont think i ever changed any gearbox bits----cam chains yes and one crank but that was it

[tbpmusic]

You need to put it together exactly as the picture shows.

Pay particular attention to part #20 - this needs to be rotated slightly once in place, to "lock" the teeth into the splines. This will affect 3'rd and 4'th gears.......
Failure to do so will cause shifting problems and possibly catastrophic damage to the tranny.
Do NOT change any of the thrust washers (I think you call them shims) from the positions shown in the drawing.
This tranny is identical (nearly) to CB200, and I also experienced a 3'rd gear problem when I accidentally got those thrust washers wrong.

[fmctm1sw]

I'll take another look at it this weekend.  I'll try to get a better photo of what I mean.  I really wish I could affect more movement from that left shift fork (or move the gears which I did)...

[fmctm1sw]

You need to put it together exactly as the picture shows.

Pay particular attention to part #20 - this needs to be rotated slightly once in place, to "lock" the teeth into the splines. This will affect 3'rd and 4'th gears.......
Failure to do so will cause shifting problems and possibly catastrophic damage to the tranny.
Do NOT change any of the thrust washers (I think you call them shims) from the positions shown in the drawing.
This tranny is identical (nearly) to CB200, and I also experienced a 3'rd gear problem when I accidentally got those thrust washers wrong.

I tried to take some better photos.. no go at this point.  Using your photo as a reference, the exact issue at hand is part 6 does not move over far enough to fully engage into part 8.  I'll look at it over the weekend.  Thanks for the thoughts to this point...

[bryanj]

Go to:-

http://www.motogrid.com/pages/parts/viewbybrand/7/default.aspx

And look up your model for a decent picture. I ain't good enough to link the exact page so you will have to go yourself

[tbpmusic]

  Using your photo as a reference, the exact issue at hand is part 6 does not move over far enough to fully engage into part 8.  I'll look at it over the weekend.  Thanks for the thoughts to this point...

I understand exactly what you say, and my comments were in exactly that context.

Did you by any chance change the countershaft itself??

[fmctm1sw]

  Using your photo as a reference, the exact issue at hand is part 6 does not move over far enough to fully engage into part 8.  I'll look at it over the weekend.  Thanks for the thoughts to this point...

I understand exactly what you say, and my comments were in exactly that context.

Did you by any chance change the countershaft itself??

I did swap the entire other shaft and gears in but I didn't mix up the shaft and gears (to this point).  I hope I can figure out what's up because there is a bunch of NOS gears on eBay right now...

[tbpmusic]

Did you by any chance change the countershaft itself??

I did swap the entire other shaft and gears in but I didn't mix up the shaft and gears (to this point).  I hope I can figure out what's up because there is a bunch of NOS gears on eBay right now...

I went through much the same thing - misplacing those thrust washers caused it to munch 3'rd gear.
So I got a complete tranny off EBay.
But for some reason, the replacement countershaft/gears I tried to use just wouldn't work, the knock pins were a hair off, and things wouldn't line up. I had to transfer all the gears from it to the old countershaft, then things worked ok.

[fmctm1sw]

Ok, back at it again.  I started over basically in taking one of my transmissions and ensuring proper assembly of the countershaft (all the thrust washers and stuff).  On this particular one, I had removed the bearing too.  What I began to notice is that I can move that countershaft left and right quite a ways. Forcing it to the extreme left and I have a real good feeling about 3rd gear but not 4th.  Forcing it to the right, I feel real good about 4th but not 3rd.  I'm hoping I can find the happy medium but I'm uncertain what mechanism is in place to ensure the correct placement of that countershaft with respect to how far left or right you push it.  Perhaps only the bearing itself?  That brass cap on the end has a slot in it but I don't recall any kind of spacer stuck down in it.  I'm glad I took a lot of pictures.  I'll see what the limit on moving the bearing itself is...

*edit*  Ahh, I think I've done it.  With the limiting factor being that clip (#22) next to the bearing on the countershaft, I put that bearing back on close to the clip and tried in the motor.  I noticed the transmission was very hard to turn.  I moved the bearing butt up against that clip and put it back in.  Not only was operation smooth, 3rd and 4th gear engage to the point I'm satisfied it will not jump out of gear.  I don't know if the "factory position" of that bearing is where I have it but it works.  I was able to effectively position the shaft using that bearing as an anchor point.

Looks like in the end, something happened that bent the "L" shift fork.  Perhaps that and maybe a PO got in there and didn't get it back together correctly.  Either way, I'm at the reassembly stage now.  Need two case bolts (snapped) and a centrifugal oil filter.  I had to destroy it to get it off.

Thanks for all the help.

[hoodellyhoo]

Hooray! Hopefully this is the end of your trans. issues. Good luck with the rest of the reassembly.

[fmctm1sw]

After I ordered a few bolts and stuff from Bike Bandit I got this back together finally today.  All seems ok now.  I got down the road through the first 4 gears without any trouble.  I didn't have enough speed or room to hit 5th.  The clutch is very stiff, just like my 350Fs started out.  They were all gummed up and I soaked them in B12 for while and sprayed them with carb cleaner.  It's improving a little already.  I hope to ride it around a little more tomorrow...