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Royal Enfield Interceptor - Knowledge Base |
| Few people seem to recognize the importance of the correct mufflers
(or silencers) on an Interceptor engine. I've compared numerous examples
of Series 1, 1A, and II machines over the years "before & after"
having correct mufflers, and the difference is startling. The original/correct
mufflers have steel baffles (rather than being glas packed), and they
allow the engine to spin up much more freely, and rev out farther
as well. Something to get discussion going ... " gREgg" What sort of baffles? I'm running mufflers purchased from Hitchcock's around 1996. You can see straight through them. There is a perforation tube the diameter of the pipe inside. I don't think there is anything else in there. Is this 'correct'? "Rick" I was wondering myself there hasnt been much action around this site. i have a 68 Ia that has the perforated inserts as you might call it. it was restored a few years ago by a friend of mine in Victoria,BC. on the topic of mufflers why are some straight and others angled up, is that to tell the different models ie. "TT Scrambler" and was that model only made for US Export? "Clive" Yes, I have wondered about the upswept vs. straight pipes myself. I have upswept on my '67 Mk IA, but that was pretty much because I like that look (very similar to a Norton Commando), and have no idea if it is "correct" or not. Not that I much care, but I am interested in knowing what is right. Cheers, "John" I am fairly certain that the straight v. upswept mufflers was a matter of the model year and specific model. As someone mentioned one model had upswept mufflers and was the TT model or something, I've seen this in magazine ads from back in the day. (Hope I don't sound like an expert, cause I'm not.) By 1967 there was one model and all of the Series 1's I've seen have the straight exhaust. The two models were offered around 1966. Anyone got one? "Rick" I wish I had my Series 1A handy so I could examine the mufflers first hand, rather than from memory. They have been of various constructions over the years, but most are several chambers connected by internal passages. What I was trying to say is that the "straight through" glas-pack style muffler generally does not work well on these engines. In several cases I have replaced the above generic type muffler with the correct factory style, and the performance improvement has been significant ... likely because of the proper back pressure in the system. The most startling improvement was a Series II that had Triumph-style glas-packs made by Campbell's ... doing nothing more than replacing the Campbell's with the proper ones made the bike feel like it had been running previously with the rear brake jammed on! Advantage is that you get good performance without too much racket ... the Factory had the tuning of the engine sorted out pretty well. Of course, there is no reason one couldn't re-tune to suit other mufflers, but why bother when the stock set up is so good? As for Burton's vs Hitchcock's, I'm in no position to judge. If Burton's is making their own, it could be that they are duplicating the original ... why not ask them? I've bought parts from both, and I'd wager what you get is dictated primarily how their sub-contractors are feeling on a given day, more than anything else. That is why I always go with NOS whenever I can. Upswept vs Straight Back Pipes: ========================= They made them both ways... the upswept style is most common in North America, and was fitted to the model known as the T.T.7 . The straight back style was fitted to the G.P.7, and all home market models. By the way, the upswept style also required a special muffler, which had a section removed from it to clear the rear axle. Something to watch on cheap replacements is this clearance is achieved by means of crude dents in the side of the muffler. Hope this helps, "gREgg" |
| Found a company in fresno, california that would coat the inside of my new pipes with a special heat resistant ceramic coating. Apparently they alum. Oxide blast the inside, apply the coating, and then cure the pipes in an oven for an hour or so. It's a thin black coating--almost looks like carbon---and can be applied only to new pipes. Cost is approx. $100 us. Haven't tried them yet but if they prevent the blue/yellow, it will be money well spent. Incidentally, the chrome exterior of the pipes is not touched. Pete |
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kbexhaust.htm
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