Manual Cam Chain Tensioner

Hey guys,

I'm after a bit of advice and/or assistance if someone wants a 6 pack of beer!

So the stock cam chain tensioner on "Project Postie" (GN250 brat/café project) gave up the ghost the other day. So never the one to do the easy thing I decided to get a friend to help me CNC up a manual cam chain tensioner. As I'm new to the whole working on bikes (swapping over from the 4 wheel varieties), I've never set one of these before. Is there anyone out there who has experience with these setting these? I've got it set and running again, but I'm not convinced it's 100% right. I'm slightly paranoid about setting it too tight and wearing the shit out of the chain and guide. I've set the valve clearances already so they're spot in the middle of their allowable range. There's still a little bit of noise there - I'm just concerned that I haven't placed enough tension on the chain.

If anyone has any tips or tricks that would be much appreciated! Or if anyone around the central city area doesn't mind having a listen and giving a hand with a fine tune of it, there's a 6 pack on offer and I'll come to you!


Cheers
Mike

Sadly, I have a poor level of mechanical knowledge... but if I come round and listen to it, can I have a beer .
Ok, not much help I'm afraid, but hope some kind soul will help you out.
Otherwise Mike at Davey Motorcycle is good and very reasonable too.

Haha, thanks Coops, like I said, it's not too bad - I was just hoping to pick the brains of someone who was experienced with these. it runs fine at the moment, and I know a little chain noise ain't the end of the world (as long as it's not slapping around horrendously) but I just want to get it spot on haha. If I don't get it sweet before I might just get the opinion of some of the guys at the next meeting on the 12th.

Nice one Mike, am I the only one with a poor level of mechanical knowledge? Changing a stator was a big deal for me... the fear of the unknown, thinking if I undo the wrong bolt the engine will spontaneously implode... I'd love to know more... is it possible to do a learn something new session on engines? Surely I'm not the only one amongst us???

You probably have a very good point there Coops, Jon and the experienced guys would have a wealth of knowledge on bike engines!! Possibly we could incorporate it with the club bike build? If the engine needs a rebuild or work it could be an ideal opportunity.

Yeah, I'll put it to Jon next meeting.
Sorry to hijack your thread 

Haha no probs mate!

Normally they just have a slipper that is pushed by a spring. You loosen off a bolt that let's the spring push the slipper against the chain and then tighten the bolt back up. On a manual chain tensioner like a primary chain I just tighten it up leaving a little bit of movement in the chain. Harder to do on a cam chain that you can't see.

Thanks Jon, yeah that's what I've been trying to do by ear and various other forms of voodo and witchcraft - too loose and it chatters and slaps around, too tight and it whines on the guide. Think I've got it close to right now, still have a slight bit of noise but it sounds a lot more like valve noise than cam chain slap so I'll try and put a stethoscope on it tomorrow and hopefully find the source for certain. Thanks!