Topic: 400/4 Cam Chain Horseshoe

[dax56]

Hello all

Bought a 400/4 a year ago as a second bike so  that I could get my hands dirty  and try to learn a bit more how they work.

From reading this forum it was pretty obvious I had the usual cam chain tensioner issues.

I've managed to strip the engine to get to the horse shoe/pivot which was of course well chewed up. I cleaned it up the best I could, and it moves pretty freely until it gets towards the end of the movement, then it sticks.

Is this usual? or should it still swing free even if rotated round to the maximum?

Are there any secrets to cleaning it up? i just managed to file off the worst of the damage, but without dismantling it - which it doesn't look like it is possible (at least not by me) I don't know how to get it any better.

Any hints/tips much appreciated.

I did reinstall the part, rebuild the engine and it fired up and ran ok. It did sound a lot quieter for a few minutes then the old cam chain rattle returned, and adjusting it made no difference.

I don't really want to run the bike if I've not sorted the problem, and destroy the new cam chain and tensioner blades that I've fitted.

I've bought another horse shoe/pivot off ebay, but it seems in similar condition to the one that's currently installed, but at least I've got one to practise on if I have to dismantle it to repair it properly.

sorry if I've rambled on

cheers

Dave

[Tim2005]

It should swing freely right to the end of the travel, but I don't think it usually travels over all that range when fitted to an engine with a good chain and tensioner blade. It seems very odd that yours has stuck again and also that it seems to be rattling so soon, I think I would just take off the rocker cover and see if the chain is still tight before doing anything else. 

You can also check the horseshoe stll moves by removing the camshaft, the tensioner blade cap (the thing bolted inside the cylinder head), taking out the blade and putting a screwdriver down onto the top of the horseshoe instead. Then slacken off the tensioner locking bolt & you can push the horseshoe back against it's plunger spring if it is not stuck.   

[RickB]

You really should try and get a hold of a heavy duty replacement. TTR400 made one, but I don't think they're around anymore. I think someone else is making them, DSS maybe?

Yep, just checked:

http://www.davidsilverspares.co.uk/CB400F-SUPER-SPORT-FOUR/part_192474/

Rick.

[ttr400]

I designed the race type part and still manufacture this, also supply these to DSS. these are out of stock right now but I have a large batch in production.

Kevin

[RickB]

Kevin,

Good to hear you're still in the game, I thought you closed up? Or was that just the other Kevin's online store?

Regardless, glad to hear you're still making your parts available.

Rick.

[ttr400]

Rick,

Yep still here. yes that was Kevin from Seattle, he is in Cambodia for a while.

Will be hitting the road myself next year on a long trip on one of my 400's if all goes to plan.

Kevin

[dax56]

thanks for the replies.

I've signed up to be notified when DSS have them back in stock, I'll just replace it then at least I know it's done right.

Any idea how long they are going to be?

Dave