250-500cc R&D HUSKY 360 HEAD

R&D Husky used to make a 360 head that had a built in compression release ( I think that's what it was anyway ) that allowed for easy starting of the big 360 motors.

They don't make those anymore, so I'm looking at making one myself. Problem is I'm not 100% sure how they worked and I was wondering if anyone can give me any insight on them ?

Maybe someone even has one they're willing to part with ?

Maybe you can find schematics on the old XR's? I know they used a decompression system.

it works using a vacuum line from the intake manifold that closes a decomp valve tapped into the head, the decomp valve is same as used on easy start briggs and stratton lawn mowers.mine was slightly off to one side of the spark plug.omg has one fitted to his bike i think.

Yeah, I was thinking it was a vac deal. So you have a decompression system on your bike?

Clogging hasn't ever been a problem on mine. It sure makes kicking a breeze. The R&D head is a completely new casting. That way they have a solid block of metal where the decomp valve goes. If you do it yourself you will be going through the water jacket. Not impossible but you probably need to do some welding.

Yeah, I've got that covered. I'm just looking for a valve now. Seems I remember seeing something about a neat little decompression valve some outfit was making, but I can't remember...........

OK, after doing some googling for the last couple of hours I have come to find that the little push button style releases like on a Husky chainsaw are the way to go. There are even spin-offs for Harley's.

I've got an old R&D head that has a crack somewhere in it. If you'd like to check it out, I can send along to you. PM me.

The decomp fitting itself is from Victa 2 stroke lawn equipment http://www.hwlr.com.au/index.php/featured-products/160-victa-decompressor

I've sourced another decomp head but have yet to fit the decomp system to it. I roasted my motor when the old head cracked or it could have been vice/versa. Motors all back and running but I need to get that decomp going or I'm not riding it. Been there, hated it. I thought about going old school with a lever and just use a fitting from an old yamaha or something but that AUTO decomp is really a nice feature. I thing you really need to route it to the carb itself and not the rubber boot as that may have contributed to my motors demise. Halls tapped the line in the crank case after it was all put together and it blew my decomp fitting apart so thats not where to route it.

Wally, where's yours tapped in?
Like this?
http://www.firstclassmotorcycles.com.au/downloads/SPEDOC1.doc.pdf

That's some great info., thanks.

This is one of the units I found. http://www.baileysonline.com/itemdetail.asp?item=QH 50371 5301
Cost wise it's looking pretty hard to beat.

This one has a pretty knob. https://www.denniskirk.com/H14197.sku

Found some that were very pricey for the Harley's, but they seemed a little over kill.

But, I do like the Auto vacuum units.

Yes, I tapped mine into the side of the carb as shown in the picks except mine is a PWK.

Thanks Wally. Its time to get this beast back in the woods. I tap in tonight. I feel like I'm riding a furnace when on the big 4 St.

Mhead,
With the push button, aside from starting, you'd be missing out on some of the biggest advantages of the auto decomp. Pop Starting. you can lock up the rear wheel of the 360 when heading into a corner, no clutch, killl the motor, then as soon as you want to get back on the gas, let off the rear brake and the beast roars to life. Also makes it much harder to stall. It'll keep spinning with barely and exhaust note.
I assume you would be remotely accessing that push button? Mines got a large tank and it'd be tough to reach that button and kick the bike at the same time. Itd still be better than no decomp at all.

Hmmm, never thought of all that. No stall easy start system. ?? ?? I was just thinking about dead engine starts at races. May just have to do the vacuum thing.

Anybody got a lead on where I can buy a decomp head for my 360?
Or any particulars on who to send mine to for addition of a fitting a auto decompression?

You use to be able to buy them from R&D Husky in Australia, no idea if they are still available.

Here is a picture of the setup on my bike:



And this post is by a member who went the do it yourself route:
http://www.cafehusky.com/threads/wr-360-decomp-head-my-way.33247

HTH

you have a decompressor head for a 360 in the picture, is it on or off the bike, I would like some close-ups as I am about to mimic it and would like to cheat if that is the case here, if it's off and you don't mind I would like to borrow it and would pay all shipping

It's on the bike but I can take it off and take pics and measure whatever you need. I know it's silly but I'm leery of sending it out because you can't get them anymore. Let me know what you'd like pics/measurements of.

mainly how the valve fits top and bottom, depth of bore and taper where it fits
if you send it UPS they are very reliable and extremely safe
it is my attempt to copy the fit design to make 2 one for mine and another for my brothers
if you send it right after Christmas it would be very safe, I need the info for a machinist

I've got a spare R&D head that's I could send out for you to check out.

I will pay shipping please PM me on this

The R&D head is one of the best aftermarket parts I have ever purchased. I can literally push start my 360 by walking beside it for a few feet. The no stall factor and easy starting especially on a tricky trail section are huge improvements to the stock head.

Good luck on this project!