Cam tensioner fitted wrongly?

[hairygit]

If I'm honest, I don't trust them anymore, misdiagnosis, mistreatment, left with permanent damage, given unnecessary drugs which caused a stroke, the list goes on! But none of it has put me iff Honda's, even though I can't physically ride my 750 at the moment, stuck with a Honda 90!

Sent from my GT-S5839i using Tapatalk 2

[Lynx]

Drew,

I'm building up my spare engine now. Here's a picture of my cam chain rear blade. Too short if anything  .

[Bitsa (Ralph Wright - RIP)]

No if I remember right that looks good if the horseshoe is fully pushed back.So when the cap is on and you let the tension-er go it should adjust correctly.On another subject Hairygit I have total sympathy for you.Similar like you I let the french have ago at my back only because there super surgeon told me if I do not have it done I would end up in a wheelchair.Well 3 years down the line I am still some days days in agony and feel shit most of the time.The only painkiller that works is scotch.I can now walk a fair bit and I can ride my bike OK so I am with you all the way on this.I just hope in time you may return to some kinda normal and bearable way of life.
Keep your chin up mate
Bitsa

[tom400f]

Let's not hijack a good thread but Jesus hairy/bitsa - get well soon lads.... 

[Drew400]

Hi Lynx,

I am by no means an expert (as many people on this forum appear to be). However, here is my experience to date, albeit on an engine that I haven't yet tried to start as it's still on the bench.

The dismantling instructions in my Haynes manual reminded me that the blade is under tension so that the cap will rise as the bolts are untightened.

When I then separated the crank cases, I was able to be absolutely certain that the bottom of the blade was sitting fully in the cup of the big u-bend cam chain bracket at the bottom of the barrels with its rubber damper in place. Thus, when I came to put the cap back on, I was satisfied that the tension I was applying by re-tightening the cap bolts was correct (with its top rubber damper in place).

Prior to all of the above, my concern was created by a picture in the same manual that appeared to show the cam tensioner sitting flush at the top of the barrels without the cap on. Hence, I was concerned about pressing down too hard on it for fear of it not being seated properly at the bottom.

Your photo looks OK to me, albeit I can't see from that angle how far above the barrels it protrudes. In may case it was about 10mm, although I didn't measure it so don't worry about (my lack of) accuracy on this.

Hope that's of some use to you.

Cheers,

D.

[Orcade-Ian]

Hi Drew,
If you refer to my much earlier reply, it would appear that you have come to the correct point, in that the blade does indeed stick up.  As I said, I don't have the exact measurement as I don't have an engine at that stage at the moment.  I ALWAYS use Honda bits (as long as they are available) but I use a wooden dowel to compress the blade via the top bracket, so that I don't put unnecessary axial load on the fairly small threads - the bolts are OK, but they are into the much softer alloy casting.  The other thing I didn't say was that I also overhaul the pivoting tensioner arm if it's been damaged/jammed by a flapping chain (I wrote an article for VJMC TANSHA on doing that)
I know you had to part the crankcases apart again after missing that starter gear lockwasher so you are now very familiar with the set up.
You will now know that the front of the chain will always be in tension as the crank drags the camshaft around, but the rear will have a correctly tensioned curve in it, produced by the bend in the blade, assisted by the 2 concentric springs - it's a good enough system, as long as maintenence is carried out correctly and after you have spent all of this time and money, I'm sure you will continue to look after it.  I will measure my next engine, which is nearing completion with all genuine parts - to act as a reference.

[Drew400]

Nice one Orcadian,

Yes indeed it's all coming back. What I admit I'm rubbish at is remembering where I read all this stuff and who from!

I think that my learning on bike building is partly based on years of general experience whereas my learning about forum usage is entirely down to this site over recent months! Hopefully readers will see past any failure on my part to acknowledge sources or link to previous discussions, etc.

Cheers,

D.

[Lynx]

The strange thing is the top of my cam chain blade is about 10mm below the top of the head. I'm sure the bottom end is located properly. Cam and oil pipes in now anyway. I slackened off the tensioner lock bolt and saw the chain ping taughter. So appears to be working OK. I'll test it before I sell it anyway.

Cheers.