Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Iron Barrel => Topic started by: Blackthou on December 19, 2007, 08:25:28 pm

Title: New Exhaust
Post by: Blackthou on December 19, 2007, 08:25:28 pm
I fitted a new system at the weekend, downpipe and short muffler. When I took the old factory system off I was surprised to see that the muffler bracket had gouged a big lump out the swinging arm.- so check yours!
I fiited the new system loosely and lined it all up in an uninfluenced state. I had to space out the upper muffler mount by about 6-8mm, the front silencer mount by 2-3 mm and the downpipe stay by 2mm or the bend fouled on the oil pump housing.
I checked and double checked all was clear before ightening everything up. Started her up and the sound was amazing. Very crisp and authentic 60's British thump. Had to reset the mixture screw (richer) or she wouldn't tick over. All ok now. Haven't road tested yet.Engine sounded sweeter due to less stress transmittted through the frame/engine by the fouling mountings.
I've got an Amal conversion for Christmas from my wife and look forward to fitting and trying it out. I intend to go out for a blast first to appreciate the improvement with the new exhaust system prior to the carb change so I can get the feel of each improvement separately. The new carb has been supplied jetted to suit the exhaust and has a freer flowing filter. I know the existing carb will run lean but still wish to see the improvement.
Will post some pictures as and when.
Title: Re: New Exhaust
Post by: LotusSevenMan on December 19, 2007, 09:21:30 pm
Watch you don't 'blue-up' that nice shiny new header pipe straight away from a lean running carb!!!!  :o
Title: Re: New Exhaust
Post by: Bullet500Dude on December 20, 2007, 12:50:19 am
Hmmmmm.  Please keep an eye on the color of the sparkplug to see how her mixture is.  She should be way lean from the decreased restriction.  Be careful not to burn a valve, or burn a hole in the piston.  I personally wouldn't ride much her until you know the jetting is correct.