Sorry Chap, the labeling on the packaging says, VDEC Decompressor kit, Universal decompressor kit for two stroke engines to fit 14mm spark plug thread. I paid £44.99 No part numbers anywhere, and perhaps they have not heard of four strokes! Cheers, ET43
Decompression devices
- Thread starter Tom Gaynor
- Start date
For years I had Royal Enfield de-compressors on my twin worked by a single handlebar lever. The disadvantages were two cables, a very small valvehead and stem and therefore rather fragile. They were short reach in a long reach plug hole so effecting compression ratio and carboning up the redundant lower threads in the head. The mechanism was worked by the outer cable with the inner cable anchored. They were ugly not very effective and using them to stop the motor resulted in a black oily mess on the cylinder heads. I removed them and had the heads welded up and reverted to the standard set up. However, I may still have them in the discard box if you are interested.
Ref. valve lifter leaks on the twin. When Tony Maughan rebuilt my engine thirty years ago he modified the external part of the valve lifter so that the sleeve no longer fitted in a recess in the timing case but fitted over an external stainless boss screwed into the timing case. I have no idea how this device works as I have never needed to investigate it because it has never leaked. Perhaps Maughan and Sons still supply this item.
Ref. valve lifter leaks on the twin. When Tony Maughan rebuilt my engine thirty years ago he modified the external part of the valve lifter so that the sleeve no longer fitted in a recess in the timing case but fitted over an external stainless boss screwed into the timing case. I have no idea how this device works as I have never needed to investigate it because it has never leaked. Perhaps Maughan and Sons still supply this item.
Hello Hugo, When I removed my R.E. bits I just put old spark plugs in the holes, The amount of people that have told me,"You won't get that going, It's got no plug leads" !! Cheers Bill.
Bill,
I should have thought of that. It would have been a damnsight cheaper!
Hugo.
I should have thought of that. It would have been a damnsight cheaper!
Hugo.
I have had exactly the same. Rapide had R.E. decompressors when I bought. I removed them after 10,000 miles as they tended to coke up (every 2-3000 miles) due to been short reach in a long reach plug hole. You could hear a whistle when they started to leak. Plugged the holes with spare spark plugs.
Had a guy jumping up and down with excitement at a rally when the bike was ticking over on two cylinders with no plug leads appearing to go to the spare plug on the front cylinder. Told him they were special plugs that ran on the wireless Bluetooth principle.
Keep thinking off firing all the plugs so twin plugs per cylinder, but the bike is running great so don't really want to start playing with ignition timing / carbs etc.
Cheers,
Simon
Hi Tom
I've used long reach decompressors (I thought they were RE, they came with a spacer so that you could use them in either long or short reach heads) since the valve lifter assembly fell apart - I don't like all those bits in the timing chest.
Most comments have already been made. They don't release much gas, so they aren't as effective as a valve lifter, but they do work for starting, and switching off the ignition means no oily mess at the top of the engine.
I've recently changed from a single cable at the bars with a junction box (difficult to adjust) to a twin pull lever, and like you I've got too many cables. I'm trying lateral thinking at the moment - I've thought of cam levers on the decompressors, but that's not very convenient - my latest thought is solenoid operation, but that's as far as I've got. I suppose that would work on the valve lifter too.
Farnell sell a small 12 V solenoid called a Black Knight - is this an omen?
All very high tech for me - perhaps I'll just put the lever on the frame under the seat (Egli).
H
I've used long reach decompressors (I thought they were RE, they came with a spacer so that you could use them in either long or short reach heads) since the valve lifter assembly fell apart - I don't like all those bits in the timing chest.
Most comments have already been made. They don't release much gas, so they aren't as effective as a valve lifter, but they do work for starting, and switching off the ignition means no oily mess at the top of the engine.
I've recently changed from a single cable at the bars with a junction box (difficult to adjust) to a twin pull lever, and like you I've got too many cables. I'm trying lateral thinking at the moment - I've thought of cam levers on the decompressors, but that's not very convenient - my latest thought is solenoid operation, but that's as far as I've got. I suppose that would work on the valve lifter too.
Farnell sell a small 12 V solenoid called a Black Knight - is this an omen?
All very high tech for me - perhaps I'll just put the lever on the frame under the seat (Egli).
H
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Hi Howard,
I don't know what sort of twin pull lever you have but the one I used had a 'wiffle tree' compensator on the standing part (same principle as the balance beam). This meant that cable adjustment was not all that critical. I probably still have it though doubtless in need of renovation. If you are interested or just want a look let me know and I'll try to hunt it out.
Regards,
Hugo
I don't know what sort of twin pull lever you have but the one I used had a 'wiffle tree' compensator on the standing part (same principle as the balance beam). This meant that cable adjustment was not all that critical. I probably still have it though doubtless in need of renovation. If you are interested or just want a look let me know and I'll try to hunt it out.
Regards,
Hugo
Hi Hugo
Thanks for the offer, but I think you misunderstood me. The single pull lever with a junction box was difficult to adjust. The twin pull (off a push bike, would you believe) is fine.
Thanks
Howard