Introducing myself and my two R65LS

[Jmo]

Hello,

first I'd like to thank you all for the knowledge you have shared.  It has helped us greatly to work on "baby blue."  I bought this 83 LS almost a year ago mainly for parts.  It was in sad shape, rusty and barely running.

Couldn't leave well enough alone and with my buddy Cris we started building a cafe. This is the result.  (more pixes at... tried to post the link but I guess forum rules don't allow until after two posts. Oh well)

Since those pixes we've installed clipons, rear sets, changed tail light, replaced right cylinder head (exhaust valve seat came loose), and that's about it.  It's a bit of a dog below 4k RPM but after that it really flies, so I have to keep shifting.  We're very happy with it and it gets lots of thumbs up.
  
The other pic is my 1982 LS that I bought new at San Jose BMW.  It's all stock except for the rear shocks and an LED tail light.  

I also have a 1988 K75S and a 1982 911SC.  I guess I'm in love with the eighties.

Jmo

[nhmaf]

Welcome aboard!

And thanks for sharing your pics!

[steve hawkins]

Great bike, hope you have alot of fun with it.

You might find messing with the jetting will restore your mid range.  Your pipes are non-standard and you probably have not got enough back pressure.  If its a Supertrap, can you add extra plates?

I opened up my exhausts some time ago, and all that was created was more noise and a hole in my mid range.  I have pod filters and run standard jets.

[Jmo]

Thanks guys.

Steve, you are right, they are Supertrapps and I really like them.  The sound is louder than stock, obviously, but manageable, and they are much lighter than the stock mufflers.  

I can add more plates if needed.  Curiously, adding plates makes it louder and it reduces back pressure.  It's because each plate has holes in it.

I started with 12 plates, didn't like the response, went down to 9 and it picked up a lot of upper range power.  I just added two more plates two days ago, to make it 11, and "seems" just as fast but need to ride it more.

You may be on to something with the jetting.  We rebuilt the carbs but kept the jets sizes as they were, figuring that at least it was running, (though not too well because one Bing had a blown diaphragm).

The sizes were 2.66 needle jet (Clymer says 2.64), 1.50 main jet, (Clymer says 1.35), and 40 idle jet.  This is an 83 LS.

My 82 LS came stock with 2.68 needle, 1.45 main and 40 idle.

So Steve, if I wanted to mess around with the jets for 83 LS Baby Blue, what would you recommend?  It's been in my mind for a while, but I don't want to lose the upper range power, cause believe me, above 4k it really flies.  I had a friend riding my K75S and on an onramp to the freeway he couldn't pass me until we got to 4th gear.  I just kept it revved up.  The bike is so light, and I guess these engines like the upper range anyway.  

Any suggestions? thoughts?

thanks

Jmo

[nhmaf]

Lowering exhaust back pressure pretty much always sacrifices low-to-midrange power for top end, and you are likely running kinda lean at the lower RPMs.    Have you installed new plugs and know how to read them?

I'd expect that going up just 1 or 2 sizes on the needle jet would make a difference, but I haven't as much experience in Bing carbs as others.  But, even before changing the needles - what position are yours set at?    IF you have a notch left for adjustment, you might first try raising the needle a notch.

[steve hawkins]

My Cafe Racer started life as a 1979, with flat top bings and clamshell air box but with post 81 heads for the bigger valves - I've lost a couple of lbs off the 'heavy' flywheel as well.  It now sports short pipes and pod fliters.  It always had a hole at 4000rpm when the bike would stutter before picking up but would run okay below and above - even before the pod filters.  I tried increasing the jetting, but that did not work.  I am back to standard jets.  I am not sure if I am standard on the needle position though....probably down 1 - leaner.

Experimentation or Rolling Road - I am afraid.  Keep an eye on your plug colour - its why I went back to very slightly leaner than standard.

[clonmore1]

Despite what I may have said on another thread (teasing nhmaf!) your bike looks really good in red!

[Jmo]

Your red beemer was one of our inspirations when we started on Baby Blue.  Damn good looking bike!

Yes, we changed plugs, twice.  First we were running the Bosch W6DC but now I've switched recently to W5DC which is a bit cooler plug.  I didn't like the fact that in my runs to the Angeles Crest the engine seemed to be too hot.

The new plugs look good after a hard fifty miles.  Light brownish.  I will play with the jet position a bit to see if a richer mixture will give more low end power.