Topic: Gear selector probs

[Skunkmiester]

Hi there, I have pretty much finished my rebuild of a CB750 K3 http://forums.sohc4.net/index.php?topic=44944.150. I thought I would give her a quick spin around the block prior to getting he MOT'd.
Starts off ok then get a horrific clanking coming from the gearbox. Sounds really bad.  Also I cannot get it into neutral.
I can start off in 1st gear with the horrendous clanking and then change up to 2nd and the bike moves forward a few inches and then the transmission locks solid.

I took off the  gear selector cover and found that the Arm stopper (Part # 13) has moved to outside the selector drum.
Whilst trying to get it back I snapped the spring stopper (Part # 17) so I'll order another of those.

However I have noted that there is a fair bit of movement lateraly (towards the engine and back)  on both the arm stopper (Part # 13) and the stopper drum (Part # . I would have thought that these would not be slack as it doesnt seem very honda like.

Can anyone please tell me if this slackness is normal? I hope I have found the cause of the problems.

[Skunkmiester]

Anyone??

I'm doing the work tomorrow so could really do with some clues.

[scottly]

You need to take a good hard look at the whole shifter assembly. Are the pins on the end of the shift drum in the proper holes? It only goes together one way, and it is a common mistake to get it wrong.

[Skunkmiester]

All put back together, new spring and gasket......and it still sounds like a heap of s**t.

Sounds like a tank track. works in 1st gear but just stops in 2nd 3rd etc. wont move at all. Also stops sometimes when I try to move bike backwards with clutch held in.

God knows what is wrong with it, I'm feeling like I may just ebay it and say goodbye to 2 years wasted. Judging by the way this thing seems to go I may just axe it and stick with my Blade.

[Cqyqte]

You mentioned rebuild, how much did you do?  Did you split the cases and disassemble the tranny?

[Skunkmiester]

Yep,
complete strip and split, I have been trying to work out what I may have put back wrong.

[Cqyqte]

Sure sounds like something is in wrong, especially if when you shift into second and the tranny locks up.  I suspect the worse my friend.  I'd take the plugs out and try cycling through the gears manually rotating the driveline by hand.  If all rotate and shift correctly then it's something else.  But you may have something internally in the wrong place or order.

[MCRider]

I'm not sure if its possible to close the cases with a shift fork out of its groove. But when you lower the bottom case onto the top one, you have to guide a fork into its gear and that may be not done.

[Skunkmiester]

Wierd thing is that it had run ok on the coup,e of times I had gone up and down the road before.

Something must have come loose. Now trying to find the enthusiasm to take the engine out and split the cases.