Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet with the UCE engine => Topic started by: Nico on October 29, 2010, 02:52:59 am

Title: Decompressor
Post by: Nico on October 29, 2010, 02:52:59 am
I read several posts mentioning a decompressor on the C5 engine.
When I look at my C5 engine I cannot see such a decompressor.
Where is it located and how does it work?
Title: Re: Decompressor
Post by: BRADEY on October 29, 2010, 06:09:05 am
It has an automatic decompressor !! The lever on the handle bar near the high low beam switch is an enricher, which is to be used only in extreme cold conditions.
Title: Re: Decompressor
Post by: raycopper on October 29, 2010, 06:12:18 am
It is automatic, and forms part of the exhaust valve cam assembly inside the engine. It works by centrifugal force i.e. it is deactivated as rpm's increase past around 300

Ray
Title: Re: Decompressor
Post by: Nico on October 29, 2010, 01:41:17 pm
My C5 does a lot of bangs when decelerating. I have the upswept aftermarket exhaust and I have been told that it is normal. But it does it more and more.
Now it starts to do several bangs in a row on a single deceleration.

Could it be related to the decompressor?

Is it possible to remove the decompressor? Can the electric starter take it?
Title: Re: Decompressor
Post by: Nico on October 29, 2010, 02:01:28 pm
could the backfire be due to the exhaust valve not sealing well?
Title: Re: Decompressor
Post by: motomataya on October 29, 2010, 05:04:42 pm
Backfires in the exhaust under decel are usually caused by an air leak introducing oxygen into the exhaust causing unburned fuel to ignite. Common with nonstock exhaust. Unlikely an exhaust valve problem. Seal it up.
Title: Re: Decompressor
Post by: Maturin on October 29, 2010, 11:37:43 pm
Could it be related to the decompressor? Is it possible to remove the decompressor? Can the electric starter take it?

Hi Nico! To your questions: No. Yes. Yes.
There are a couple of postings regarding backfiring and aftermarket silencers.
http://www.enfieldmotorcycles.com/forum/index.php/topic,8756.0.html
http://www.enfieldmotorcycles.com/forum/index.php/topic,7909.0.html
And some others I didnĀ“t find in the last 3 min
Greetings Maturin