Forum

[Zitman]

Hi all,

Approaching the end of the rebuild on my 535 Bullet and have a strange problem. I have changed the bars and got rid of the switchgear including the left hand side one with the decompresser level. I have got a nice replacement but it seemed to be keeping the decompresser open and leaving me with no compression. I have completely remove the lever now so just have a loose cable. I have compression and I can press the top of the decompresser on the head itself and ease it over TDC but then the compression seems to disappear again. If I 'jiggle' round with the decompresser it seems to be OK again. It seems as though the decompresser itself is sticking but it seems free. I have had it to bits, cleaned it and put it back together but to no avail. Any thoughts?

Z

[Alan R]

Hello ZITMAN ---- I've had a de-compressor valve where the stem had a slight bend in it---just enough to make it "Semi-sticky" if you get my drift ?? How about fitting an AMAL-type lever (choke type ) on the handlebars ??--or you could remove it altogether and fit our hosts blanking plug kit.??

[Norm]

Alan,
plugging the decomp not a good idea with a 535, bit too hard to get it over TDC. The little one finger lever early decomp type are the best if you have room to fit them because you can keep you hand on the handlebar and just pull on the lever then let it go

[Alan R]

Hi NORM----- Yes, I know the type----my 2 mates ( fully paid-up members of my "mates" club, no less !! ) have them on their Ex-WD BSA B40 350's.

[Zitman]

Thanks both,

The lever I have bought is the single finger older style. But I think the problem lies with the body of the decompresser (the bit in the head) as it doesn't seem to release even when the cable is not connected to the lever. And when the decompresser worked, I used to be able to stand on the kickstart when it was at TDC and it stayed there and I am not exactly svelte!

I am thinking a new decompresser body or stronger spring may be in order.

Cheers

Z

[Alan R]

------------- just a thought }--- remove the de-compressor unit ( you are going to do that anyway) and pop a spark plug in---I believe it's the same thread ??... Now you can cold-test the compression and prove the de-compressor faulty (which it probably is ).

[another Allan]

Will a spark plug block both holes? The inner hole that vents compression into the exhaust port also needs blocking.

[John R]

They can get coked up. I would remove it, dismantle it, clean it, see what you think and replace it or get a new one if it seems damaged or bent.

[Zitman]

John, That's the strange thing I did remove it, strip it and clean it and I made no difference. Might have to talk to our hosts and see how much a new one is.

Cheers

Z

[Phil Ashbrook]

I removed mine and welded up the exit port , I regret that now as I have an engine in a high state of tune at 9:1 comp ratio and a close ratio gearbox with 1 extra tooth on the front sprocket , kickstart ratio is higher and I can stand on the lever for 30 secs before it gets past TDC .