The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: its_only_me on March 17, 2007, 02:33:53 PM

Title: Blimey these bikes are Exhausting.
Post by: its_only_me on March 17, 2007, 02:33:53 PM

Does it make a difference to the bike whether the exhaust has one or two crossover pipes in the headers?


I ask as there is this pair of stainless headers on the UK e-bay but they have the single cross over, and I am sure my 65LS has two? also is this one the right size for an LS as I have not measured my pipes.

here is the e-bay number...

110103900037

Title: Re: Blimey these bikes are Exhausting.
Post by: Mumford on March 17, 2007, 03:46:22 PM

I'm sure there are people with better knowledge on this, but I'll toss my bit in. I *believe* that the crossovers play a role in the engine's power characteristics, and are there for a reason. I'd not be comfortable switching to a different setup without knowing more. Also, many things for the R65 are not the same as for the rest of the R bikes, and as such I'd be a bit hesitant to get parts that aren't specific without first crosschecking. Also. . .it seems possible to repaint your headers if they're not completely shot, I have 150 miles of mixed conditions on mine since the repaint, and they're holding up well.

Title: Re: Blimey these bikes are Exhausting.
Post by: Baffo on March 17, 2007, 06:38:42 PM

Front balance pipe is for torque low revvs, rear balance pipe is for torque higher revvs
Also, apparently, you need at least one of these to get a boxer to idle correctly

Title: Re: Blimey these bikes are Exhausting.
Post by: Justin B. on March 17, 2007, 07:26:52 PM

From what I understand the front one is the most important, from a "streetability" point of view.  Our 1980 has the single crossover while the others have the dual.  If you can get a good buy on the single crossover headers I wouldn't hesitate using them.  BUT, they gotta be for an R65...

Title: Re: Blimey these bikes are Exhausting.
Post by: Ed Miller on March 18, 2007, 12:58:05 AM

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&viewitem=&ru=http%3A%2F%2Fmotors.search.ebay.com%3A80%2F%3Ffrom%3DR40%26satitle%3D%2B110103900037%26fvi%3D1&item=110103900037

Sorry, I've never messed with the tinyurl stuff.  My browsers never have problems with long urls.

I would be pretty paranoid that those pipes would not fit an R65, as nearly all the other R series bikes share pipes in common, but not the R65 and R45.   He does say he's breaking (I wish they would use a nicer word!   :'(        )R65s and R45s, so maybe.

Dunno why they went to two cross overs.  Mine has both, and I wouldn't replace them with singles, as I doubt BMW did it as a money saving move.  

Title: Re: Blimey these bikes are Exhausting.
Post by: its_only_me on March 18, 2007, 02:36:06 AM

Thanks, I have looked into this and they are the wrong size for the 65 series bikes, we need 35mm not 38mm .

Title: Re: Blimey these bikes are Exhausting.
Post by: Baffo on March 18, 2007, 04:55:50 AM

Quote

From what I understand the front one is the most important, from a "streetability" point of view.  Our 1980 has the single crossover while the others have the dual.  If you can get a good buy on the single crossover headers I wouldn't hesitate using them.  BUT, they gotta be for an R65...

More or less important, my R65G/S only has a collector behind the engine, no front pipe and one lefthandside muffler. Which I'm going to change to single front pipe and 2 megaphone mufflers. I was thinking of a rear one also, but the design for the bit between headers and mufflers is still in debate between me, the welder and the tuner  ::)