Kibblewhite compression releases

seattle##gs · Apr 25, 2024

A friend has a really hard time kickstarting his 850 and someone else who weighs only 140 has a hard time with her 750. Booth of them would like an easier time of it. I have a 750 motor in a Trackmaster frame with no center stand and it is almost impossible to kick over.
** Using it with the electric start it takes a lot of strain off the starting components and battery.
** It is cheaper than an starter motor kit.

lcrken · Apr 25, 2024

NORTSTER1974 said:
Try doing this. T.C. of Hogslayer fame RIP used to do this modification. I can't remember whether he wanted $500 a hole or $250 each. He did say he had a jig and it was important to get it placed right in the combustion chamber. Between the plug hole and head bolt. I don't know if his shop still exists? Sunset Motors. Google

This is what the installation looks like in the combustion chamber. I don't recall where I got this image, but I think it is one of TC's conversions.

Ken

Dan1950 · Apr 25, 2024

lcrken said:
This is what the installation looks like in the combustion chamber. I don't recall where I got this image, but I think it is one of TC's conversions.

View attachment 114003

Ken

Silicone on a head gasket!

Flatspot · Apr 25, 2024

baz said:
I believe the bigger panthers have a half compression lever on the side of the engine

I had a 600Panther and it had a small lever which held the exhaust valve slightly open, reducing the massive 6 to 1 (or was it 5.5-1?) to almost atmospheric. It could then be ‘kicked’ over by hand. It is the lever just below the red paint

Richard Tool · Apr 25, 2024

My ES 2 ( 500 cc single ) has an original compression release as did most of that era. Often referred to as a valve lifter . It is elegantly simple in it’s design. There is a shaft that crosses the exhaust rocker . The shaft has a flat milled on it’s underside so that it clears the rocker when the rocker is in it’s upper ( valve closed ) position. Pulling on the release lever rotates the shaft so that the corner formed by the intersection of the flat and the side of the shaft acts as the lobe of a cam and pushes on the rocker , holding the exhaust valve off it’s seat . Of course this is easier to engineer on a single than a twin but I wonder if something simple could be made to work on a Commando.

Flatspot · Apr 25, 2024

I forgot (it’s an age thing) the Panther also had a decompressor lever and cable, something in my dim and distant memory makes me think it was how I stopped it.

baz · Apr 25, 2024

Flatspot said:
I had a 600Panther and it had a small lever which held the exhaust valve slightly open, reducing the massive 6 to 1 (or was it 5.5-1?) to almost atmospheric. It could then be ‘kicked’ over by hand. It is the lever just below the red paint View attachment 114004

Yep that's what I've seen
You flip the lever over and start the bike on half compression
Then you flick it back once it's running if I'm correct?

Flatspot · Apr 25, 2024

baz said:
Yep that's what I've seen
You flip the lever over and start the bike on half compression
Then you flick it back once it's running if I'm correct?

Yes it is.

johnny Lagdon · Apr 25, 2024

My Vincent twins have them, pull the lever in, kick it over a few times to charge the cylinder , bring up to compression, release the decomp lever and off you go

maaseyracer · Apr 25, 2024

My dad has these on his Rickman Triumph. 80 year old guy with leg braces and neuromuscular disease can kick start his 11:1 compression, almost 800cc Triumph. Once fired and running you have no idea they are there. I don't even try to start the bike anymore without them. Also the homemade advance retard lever on the ARD Mag helps. Prior to the compression releases and timing lever I had a kick with the advance locked in a 39 or 40 degrees that had me on the ground questioning choices I have made in my life.