1984 Katana 7/11

[Guest]

Well, a little bit of both in this instance.

Second gear is a press fit on the countershaft, held in place by friction and high strength thread locker.

They say you can replace the gear twice before having to replace the shaft, and due to first being integral with the shaft, to replace any other gears you need to press second off and back on again, and of course I have no idea how many times that may have been done already. In this case fifth needed replacing, so second had to come off.

When we got second off, we noticed marks/burring on the shaft and inside of second that indicate it may have spun a little already.

So, given all the above, welding was the recommended course of action and is a very common fix to sort the issues.

In my mind it's also part of trying to make sure the bottom end is as solid as can be to avoid needing to pull it apart again any time soon.

[dorkburger]

Got it. Thanks.

[Guest]

No worries!

Stuck the bearing in the oven for 10 minutes tonight, grabbed the countershaft out of the freezer, and it literally dropped into place. Too easy!

Yes, you can see frost on the countershaft

Untitled by starpoint73, on Flickr

I did the test fit with the lower case and it all went together nicely, however it just doesn't seem to want to shift via the shift lever.

If I rotate the shift drum by hand it seems to move just fine, just not via the shift lever and cam on the end of the drum.

Any thoughts or tips on what I may have screwed up here? Pretty sure I've assembled it right but there might be some trick I'm missing.

Untitled by starpoint73, on Flickr

[Sam 78 GS750]

Check to make sure that the shift pawls aren't backwards. Keep the round part at the bottom, but try switching them around. The two aren't interchangeable. One is meant to go on the top, and one is meant to go on the bottom. I had the same issue, and that's what it was for me...

Also, doesn't the shift lever insert from the side that's in the pic, not the other side?

[Sam 78 GS750]

I'm talking about #6 and #7 on the fiche here --->https://www.partzilla.com/catalog/su.../gear-shifting

[Guest]

Cheers Sam, I was pretty sure I'd got those right but being the first time I've assembled this gearbox there's no guarantees.

I saw that the pawls are designed to go in one way only by the recess for the spring, but I'll revisit for sure.

You're right on the shift lever shaft, but I'd removed it before taking that pic so it didn't obscure any pertinent details of the cam end on the shift drum.

[Guest]

Man I'm so confused with this gear shifting...

I'm definitely going exactly by the book, and the pawls on the cam end are definitely in correctly.

The shift drum is definitely in neutral with the neutral stopper sitting in the indent.

The cam end is set so the pawls are engaging in two of the recesses.

Untitled by starpoint73, on Flickr

If I slide the shift shaft in, no way is everything in a neat centre line, the cam end is definitely offset, and rotating the shift shaft runs out of shifting room real quick, and I know that's not right.

I know however this goes together it should be a short movement up or down, with the cam end being spring loaded and all basically selecting the next set of recesses to rotate the shift drum around.

I'm just not getting it...

Untitled by starpoint73, on Flickr

And of course if I set the shift shaft and cam end with the right alignment, the pawls are between recesses so all the shift shaft does is move it to a recess and it doesn't spring back again.

Untitled by starpoint73, on Flickr

I'm just so damn confused... can anyone enlighten me?

[Guest]

Ok, no idea what I did wrong the first time, but I put the retainers on, slipped the shifting shaft in, and good as gold.

Did the test fit to the upper case and gearbox again, and shifts fine from 1st to 5th and sits in neutral happily as well.

Looks like I'm good to put the cases together this week, so I ran a tap through all the crankcase threads as well last night to give them a clean up and they all feel good too.

[nvr2old]

An older, wiser mechanic that I used to work with at a Honda dealership used to watch me at times (more then I want to admit) struggle with something that he could do with his eyes closed and one hand tied behind his back. He would patiently watch me get to the point of literally throwing a wrench. Instead of doing it for me he would tell me, these are precision machines, they only go together (correctly) one way. His advise was always to walk away when you get frustrated, think about it a bit, and 99% of the time that worked. He was one of the best mechanics I've ever known.

[Greg B]

I was going to suggest installing the retainer.
The retainer probably restricts any end play in the drum.
I imagine the either drum, or the shaft was trying to move outward ever so slightly, and causing a bind.

[Guest]

That's excellent advice Larry! Walking away from things has helped me many times over the years... much better than getting a bigger hammer

Greg, definitely a good possibility there, and I think adding more oil definitely helped too. Something I forget sometimes while test fitting these bits together is that the engine has lots of oil on all the bits, and typically the gearboxes don't shift too well without the motor spinning also.

I gave myself a night off last night but hopefully tonight I can get the bolts and gasket surface cleaned up ready to put the cases together.

[Guest]

I had an exciting night last night... cleaned the crankcase gasket surfaces up then cleaned and sorted the crankcase bolts.

That does mean the cases should be ready to go together tonight though!

Untitled by starpoint73, on Flickr

[Greg B]

I'd go ahead and install APE main bearing studs, and cylinder studs & nuts. More peace of mind.
Although to do all that would probably run a couple hundred bucks. Not including shipping. And do you guys pay a VAT down there?

[Guest]

I'd love to Greg but that would set me back a couple of months at this stage. I've pretty much hit the end of the available $$ for now and I can only put a certain amount away each month towards the build. I can't see finishing this year as it is factoring in the things I have to do already unfortunately. I think I'm going to hit a point where I have a running Kat waiting for the last items like tyres and chain and sprockets.

I did get the cases together last night though.

Untitled by starpoint73, on Flickr

I had to stop short of putting the sump cover on because I discovered I hadn't ordered the O ring that sits between the cover and the lower case.

I'll get that as well as the O rings for the oil pump and pressure switch ordered today, hopefully they're in stock and not back ordered again.

[Sam 78 GS750]

I hate waiting for o rings and little things like that... some good progress going though