The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Motu on August 10, 2009, 03:24:43 AM

Title: Supertrapp.
Post by: Motu on August 10, 2009, 03:24:43 AM

I fitted an IDSII Supertrapp on my mono R65 last week.Not a great 2 into 1 - I would have preferred to make one up with U bends and a collector,but as there is an exhaust shop a couple of doors up from work I thought I'd get him to bend me something up. Not a good idea without the bike on site....it needed a rebend and a bit of tweaking,and is not a great looking system.He just bent up the pipes,and I welded it up and into a cone collector.I had it all done - and then took it off the centre stand - duh.So who needs a gut stand anyway?

My old reverse cone megaphones were pretty noisy (99db at 2,500 rpm...100db limit...it's my job) and I didn't like them at higher rpm's.The Supertrapp is 97db with 8 discs (we actually fail at 97db,then they need to be certed as under 100db) and the noise is pretty constant throughout the revs...no more snarl and drone at higher revs.

I find I am riding the bike much harder,as the sound isn't so overpowering at higher rpm's...it's behaving like a short stroke engine should.Now I let it sing at the red line - on a twisty up hill climb I'll go to the redline on the short straights,take the corner at 6,000,then charge out of the corner into the next one.Before I would have upshifted to stop the noise.

The bike seems happier at all rpm...and I can hear the gearbox whine now! I had lifted the needles for the megaphones - I'll run it for a while and then check the plugs,but it seems to be running just fine.

Title: Re: Supertrapp.
Post by: nhmaf on August 11, 2009, 12:49:34 AM

I'm sensing a bit of Burt Munro's spirit is alive and well...
though the purists would be aghast at Supertraps on an airhead!

Title: Re: Supertrapp.
Post by: bruce_launceston on August 11, 2009, 06:29:10 AM

I'd love to see a photo, I have considered making a 2 into 1 as I have a great looking stainless steel muffler off a late model guzzi 1000 that I could use.
I built the 2 into 2 headers on my LS from standard exhaust bends, they have been on there about 18 years I think. . .  and speaking of Burt Munro I went and found the real 'World's Fastest Indian' at its home in a hardware shop in Invercargill last month when I was holidaying in New Zealand. I also saw Ivan Maugher's gold plated Jap speedway bike. New Zealand certainly had a few world leading motorcyclists.

Title: Re: Supertrapp.
Post by: Motu on August 12, 2009, 01:27:15 AM

I would have preferred to make it out of mandrel bent U bends,the pipe bender can't do as tight an S curve and distorts the pipe.This will do for now until I get bored and want a change again.Looks are not too important for me...so long as it does the job she'll be right.

My camera is being repaired,I'll take a photo when I can afford to get it back.

Title: Re: Supertrapp.
Post by: Motu on August 27, 2009, 04:49:26 AM

So I got my camera fixed,and here is my version of a 2 into 1.

(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fimg398.imageshack.us%2Fimg398%2F9339%2Fp8270189.jpg&hash=f6c465d43114163dc273465a01e3a5339061d702)

(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fimg398.imageshack.us%2Fimg398%2F1038%2Fp8270190.jpg&hash=e99b816e8cf8e67625c907ed0a9e31adf1d23779)

Title: Re: Supertrapp.
Post by: nhmaf on August 29, 2009, 12:45:19 AM

I am sure that it is much lighter than the stock system - and LOUDER, too!
 [smiley=bmw_smiley.gif]