250-500cc wr 360 decomp head my way.

Here are some pics of the 360 heads I have.

My decomp head is only welded on the outside, it just has a hole in the combustion chamber side, no weld. It must have an o-ring of some description inside maybe???

Looking to get my spare head welded on both sides like in this post.

The decomp head was cut 40 thou (215psi) and needed a different spring in the decomp, it was closing too early.

Also the vacuum is disconnected, the valve closes on its own when the motor starts.

Cheers.

My 360 has the Victa mower decomp fitted and it works well. It even bump starts easy if you panic brake and stall the engine but are still rolling.
I cant get the long version decomps in NZ any more either.
Mine has just the external weld and internal O ring, which you need to change every time you do a piston.
It breaks down and eventually leaks causing grief as I have found out.
When I do my next overhaul I will get the head redone, welded inside and out plus taller for the short decomp.

Mike

I did something similar with a manual compression release but the work I had done screwed up and I was only able to use it for a few hours before it leaked so much coolant that it was unuseable. There is nothing better than a manual compression release for going down steep, rough hills. I have finally cured the "difficult to start" nature of this bike with a 2016 TE300.

Well i can't imagine how the oring one side and weld the other works, in that picture hooosk there looks like different color ring of weld around your hole. I would think that it was recessed and welded then re profiled.
Looks like a proper job.
Re orings wtf!?! Really want to see how they managed to that.

The short Victa decomp fits with 2-3mm from the spark plug boot.

My long decomp valve broke, all I could get at the mower shop was a long version.