Norton Commando Peashooter Silencers/ Mufflers

Byarchie

XS650 Member
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England. Essex.
Hi everyone. I am fitting a pair of these to my 76c 650 as my pipes have rotted out. Wondered if anyone has had experience of jetting up for them. I am using std air filters, std headers, bs38s and currently std jets 122.5 main, 25 pilot and 4mi needle. A good starting point would be great i know every bike is different and there are other aspects to factor in. Naturally these will be more free flowing pipes.
 
I have peashooters on the stock pipes. I have gone up to. 27.5 idle and one size larger main. I should have bought larger jets to try although the engine runs fine. I will note I have difficulty getting CV carbs to the ultimate fine tuning because they compensate slight mixture imperfection by design.The needle is raised one notch. I have K and N filters. Points and Premium gas. Old battery so I kickstart.

The sound will be loud and ripping. It will sound nothing like a Norton, I had one. My bike seems to be more difficult to short shift, although it runs fine at very low rpm, yours may be the same. The engine seems like a higher rpm engine. My original '77 mufflers had the cap knocked off the exit tube so were more free flowing than stock. Great sound.

I think I covered most bases. :)

Tom
 
I have the same experience as Tomterrific. An XS650 with Norton Commando sounds totally different than a Commando. Or an XS or a Bonneville for that matter. On my 1977 D model, I fitted single wall aftermarket headers with 1,5 " Outside diameter and 1 3/8" inside diameter, and a pair of "big bore" Commando mufflers for 1 1/2" headers. Commandos actually had smaller headers, 1 3/8" outside diameter.
In any case, the sound from my setup is horrible, almost like a 2 stroke with a bad muffler.....So I cut my peashooters apart, and removed the louvered core, and replaced it with a perforated core. The plan is then to wrap the core with muffler fibreglass packing, and machine a beveled ring that fits inside the megaphone and reverse cone, and use SS pop rivets to hold everything together. Hopefully I will get this done sometime in February.
 
I have the same experience as Tomterrific. An XS650 with Norton Commando sounds totally different than a Commando. Or an XS or a Bonneville for that matter. On my 1977 D model, I fitted single wall aftermarket headers with 1,5 " Outside diameter and 1 3/8" inside diameter, and a pair of "big bore" Commando mufflers for 1 1/2" headers. Commandos actually had smaller headers, 1 3/8" outside diameter.
In any case, the sound from my setup is horrible, almost like a 2 stroke with a bad muffler.....So I cut my peashooters apart, and removed the louvered core, and replaced it with a perforated core. The plan is then to wrap the core with muffler fibreglass packing, and machine a beveled ring that fits inside the megaphone and reverse cone, and use SS pop rivets to hold everything together. Hopefully I will get this done sometime in February.
Try adding a balance tube before the fiber glass packing. The added muffler volume should tone it down.
 
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