The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Ash on April 29, 2008, 02:07:07 PM

Title: Wet worries...
Post by: Ash on April 29, 2008, 02:07:07 PM
Have ridden my bike through some of the worst of the British weather for 1000 miles two weeks ago with no probs, but having a few carb issues (reluctant reving over 3500ish when cold in the mornings) someone who used to own an R65 recommended removing the float bowls and cleaning them out - which I did. Some water+gunk in there but not too bad at all (should there have been a gasket there?)

Twice now though, in massive downpours, the bike has not wanted to run smoothely or without popping outside of a 2000-3500ish rev range. Do we think this is carb or electric related?

Cheers,
Ash
Title: Re: Wet worries...
Post by: Justin B. on April 29, 2008, 03:08:09 PM
Could be plug wire or coil related.  It would help to know the year...
Title: Re: Wet worries...
Post by: Ash on April 29, 2008, 03:19:20 PM
Sorry - should have said its a 1981 with around 38,000 on the clock.
Title: Re: Wet worries...
Post by: Rob Valdez 79 R65 on April 29, 2008, 04:57:47 PM
Yes, you want cork gaskets on your float bowls.

I believe the '81 was the first year to have the coil that was notorious for cracking.  Check it closely.  Replace it if you determine it is the original.

If you have the spark plug caps with a metal cover (http://i16.ebayimg.com/04/i/05/7c/91/a3_1.JPG), that could be suspect.

I always suggest NGK caps and wires.  I use their plugs, too.

Here is a thread you may find helpful:
http://suraklyn.com/yabb/YaBB.pl?num=1191053968/9#9
Title: Re: Wet worries...
Post by: nhmaf on April 29, 2008, 11:06:29 PM
Yes, the 81-82 years was the season of the "crack-omatic" coil - check the coil and examine as Rob recommends.  Look for the part number
stamped on the aluminum bracket (check out this thread, if the number ends in "200" as shown then it is one of the notorious OEM coils)
http://suraklyn.com/yabb/YaBB.pl?num=1195434246/3#3

Even though my coil had carried me through some incredibly wet storms, it was only a matter of time - looking closely at the pictures
in this thread you can see the fine lines of cracking that are a sign of impending failure.
Title: Re: Wet worries...
Post by: stevie on April 30, 2008, 02:42:58 AM
Hi guys and gals

Whilst l had the tank off my 65 at the weekend I noticed the front coil (nearest the headstock)on my 80/81 bike is being held on with a piece of twisted up wire. On closer inspection it looks like the fixing on the frame has corroded and broken at some point. Do any of you guys have a suggestion of a more substantial/satisfactory solution to my dilemma. As always all advice appreciated (especially when accompanied by photos)

thanks Steve
Title: Re: Wet worries...
Post by: Justin B. on April 30, 2008, 07:35:26 AM
A long hose clamp would probably work if you weren't inclined to do a permanent and proper fix.  I think I have cable-ties on my '81 R100...
Title: Re: Wet worries...
Post by: montmil on April 30, 2008, 10:58:43 AM
Quote
...  I think I have cable-ties on my '81 R100...

Ah, cable ties, aka zip ties, etc. The coat hanger wire for the 21st century. Back in the day, I hoarded them because, for my young family and I, they seemed terribly expensive. Nowadays, I keep several thousand, yes THOUSAND, in my shop... just because I can. ZIP ON, bros!  8-)
Title: Re: Wet worries...
Post by: Bob_Roller on April 30, 2008, 11:02:27 AM
I saw the next generation of zip ties in a recent Harbor Freight advertisement, stainless steel !
Title: Re: Wet worries...
Post by: Ed Miller on April 30, 2008, 12:38:16 PM
I saw those, too, Bob, and of course I wanted them.   :-[  

It's a good thing I don't like driving in Salem, or I would be up there way too often!

Title: Re: Wet worries...
Post by: Rob Valdez 79 R65 on April 30, 2008, 06:31:31 PM
Quote
Hi guys and gals

Whilst l had the tank off my 65 at the weekend I noticed the front coil (nearest the headstock)on my 80/81 bike is being held on with a piece of twisted up wire. On closer inspection it looks like the fixing on the frame has corroded and broken at some point. Do any of you guys have a suggestion of a more substantial/satisfactory solution to my dilemma. As always all advice appreciated (especially when accompanied by photos)

thanks Steve

The front coil mount pretty much always broke on any ['78-'80] R65 that got ridden.

I used zip-ties for many years.  For me, this was an unsatisfactory solution.  
I could not find hose clamps long enough in the bins at the hardware store, but while looking around in the plumbing department, I saw these giant rubber fittings, 8-10" in diameter, and they came with hose clamps!  I just measured the distance around the frame and the coil, and went back to the store with my information.

Since your front bracket broke, that means that a previous owner must have relocated the main ground wire for your wiring harness.
You will want to examine this connection carefully.  Make sure everything is shiny and clean.  DIELECTRIC GREASE!
I mentioned this in a previous post (http://suraklyn.com/yabb/YaBB.pl?num=1198915890/0#0).
Title: Re: Wet worries...
Post by: steve hawkins on May 01, 2008, 03:13:18 AM
Me,

After several broken clamps and finally both the mount points failing on the frame, I ditched the 2 Bosch Blues from my bike (1979 R65) and replaced them with a twin output coil from a BMW K100.  This I have bolted on to the 'relay tray' close to the front coil position.  The K100 coil was sourced second hand and has been fine so far.

Steve H
Title: Re: Wet worries...
Post by: stevie on May 01, 2008, 10:29:25 AM
Thanks guys just a couple of questions- Rob, as I am electrically challenged could you tell me what colour the earth wire is ? Steve- the K100 coil, do you have any photos, and is it just a case of plugging in the various cables/wires then positioning the coil?

thanks guys, Steve.
Title: Re: Wet worries...
Post by: Bob_Roller on May 01, 2008, 10:36:25 AM
The 'earth', or ground wires are brown on our bikes, unless a previous owner has been in there messing with things !
Title: Re: Wet worries...
Post by: stevie on May 01, 2008, 10:40:10 AM
Cheers Bob. Sorry to keep going on like a stuck record but noticed some mentioned a k75 coil would do. Is this right with it being a 3 cylinder bike? Also there is an R80st coil for sale on ebay over here in the UK would this also suffice?

Regards Steve.
Title: Re: Wet worries...
Post by: Bob_Roller on May 01, 2008, 10:53:12 AM
The K75 has three coils, so you would need two of them, if you go that route.

The K100 bikes had two dual output coils, that seems to be a route a lot of riders use if the coils are available at a reasonable cost.

Only concern with the R80 coil, is that you may get an old grey coil, as all of the twin cylinder airhead bikes used the same dual output coil from 1981, up until the oilhead series bikes came out, if my memory is correct.

My original grey coil failed at 13 years, the OEM replacement coil , the red cased one, only lasted 10 years, so I'm not a real fan of the OEM coils, I installed a Dyna 'brown' coil from a company called Motorrad Elektrik, located in the southeastern US for $86US including a mounting bracket.