cam chain benly

[Usher4566]

In the next couple of mounths I may have a go at top end on my benly .the question is how do I go about the timing chain ? How do I get it se right when put all bck together?
____________________
New cd200 benly owner

[TGB]

cam chains are not a job for the amiture home diy. as these cam chains run through the centre of the two cylinders. and is too technical to explain in words over the forum and the tools needed are complex. so my advice is have a pro do the job.

[Usher4566]

It's a benly not a NASA rocket shit I don't need speacail tools
____________________
New cd200 benly owner

[von1papen]

From someone who has just rebuilt the top end of a cm200, I can tell you now the cam chain is a pain in the hole!

There is bugger all play in the chain so we found you had to lift one link at one end of the cam sprocket and carry this on like a mexican wave until the other end, moving the sprocket round by one tooth, continue doing this till cam assembly and sprocket are in the correct position! (with the wee cut out facing the 3 o'clock position)

Removing it in the first place isn't too bad, like I said its just getting the correct timing that is annoying when you've put it back together because of the lack of room to work and tight tolerances.

I throughly advise getting a 6 sided socket for the 12mm nuts that hold the rocker assemblies on, they can round off easily because they're torqued down plus they hold the whole top end together more or less.
If you find the edges are in any way beginning to sheer off on the nut when using a 12 sided standard socket for the love of the lord, STOP. (someone had done this to one of the nuts in my engine)

However, it is all worth it! I rebored the barrel, fitted oversize pistons and lapped the valves and she now runs beautifully

[Usher4566]

[von1papen]

Theres a wee cut in section in the cam assembly rod end (best way I can think of describing it) that must be at the 3 O'clock position when the pistons are at TDC, ensuring that they open and close at the right times! The Haynes manual is invaluable

[Usher4566]

[von1papen]

There is a 'T' mark for TDC when you taken the points cover off, you can see it through a small aperture, you'd use it when setting the valve clearances!

Once this is set you then have to get the cam assembly cut out in the right place by moving the chain along the sprocket till it sits in the right position at TDC

Manual will explain/show it better than I can

[MarJay]

[Usher4566]

Thanks yea seems strait forward
____________________
New cd200 benly owner