The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: qwerty123 on July 24, 2017, 01:43:02 AM

Title: Shift lever suddenly feels lighter?
Post by: qwerty123 on July 24, 2017, 01:43:02 AM
Hi all,

Towards the end of my cross-country ride I noticed that the shift lever suddenly felt lighter. I think it's in both the up and down directions.

I immediately thought of a broken spring, but everything seems to be working just fine. I put 120 miles or so on the bike today, with plenty of shifting through the twisties along California's coast.

The R65 fiche mentions three springs:
--#4, P/N 23 31 1 231 618, "Gear change return"
--#7, P/N 23 31 1 242 910, "Shank spring"
--#17, P/N 23 31 1 234 791, "Gear change return spring"

From the fiche alone I'm having trouble puzzling out what each of those do, but I'm wondering: could it be that one of those three has broken, and that's what has caused a noticeably lightened lever? My assumption would be that if one were broken shifting wouldn't work at all.

I suppose it could also be something in the linkage, like the long bolt that goes in to the transmission loosening, or some such...

Any ideas, R65 brain trust?


Title: Re: Shift lever suddenly feels lighter?
Post by: Barry on July 24, 2017, 06:09:58 AM
Touch wood I've never had the infamous pawl spring break so I'm not much better off than you in that I can only go off the diagrams.

My understanding is that #7, P/N 23 31 1 242 910 is the pawl spring and as you can still change gear I assume it's not this one. So it must be one of the other two gear change return springs
Title: Re: Shift lever suddenly feels lighter?
Post by: georgesgiralt on July 24, 2017, 08:04:34 AM
Hello !
I've had the infamous pawl spring broke twice on me.
I've been told that one cannot say what spring is broken before opening the gearbox or finding the broke parts in the oil.
This is because there are a couple of possible assembly in the gearbox change mechanism and you can not vouch which one you have before you open the box...
I bet that if you have the early system, you did not broke the pawl spring otherwise you could not change gears...
I would change the oil and see if you get metal parts coming out. If something comes out, it is time to open up....
Title: Re: Shift lever suddenly feels lighter?
Post by: qwerty123 on July 24, 2017, 06:32:29 PM
The system is from a 1984, and I have no reason to believe that the gearbox has ever been open. Based on my research that means I have the newer pawl system, I think.
Title: Re: Shift lever suddenly feels lighter?
Post by: mrclubike on July 24, 2017, 08:50:20 PM
What about the detent roller coming apart
Title: Re: Shift lever suddenly feels lighter?
Post by: qwerty123 on July 24, 2017, 10:26:57 PM
That's a very good point, it could easily be that. I probably have the plastic one, too. I've seen recommendations to switch it out with the metal ones from K bikes. Hmmm...
Title: Re: Shift lever suddenly feels lighter?
Post by: Motu on July 24, 2017, 11:58:11 PM
Hairpin springs can crack before they finally break, and they will feel weak then.  A couple of weeks before my pawl spring broke I couldn't get 1st from neutral, but could from 2nd, and all other gears were fine. I think being weak it just couldn't pick up 1st.  If the spring that returns the lever to centre is cracked, it could feel lighter. Any of the 3 springs is a gearbox stip anyway...the shift mechanism is the last thing you remove from the box.
Title: Re: Shift lever suddenly feels lighter?
Post by: Matt Chapter on July 25, 2017, 01:00:18 PM
How many miles are on the transmission? Maybe it's finally broken in!
Title: Re: Shift lever suddenly feels lighter?
Post by: qwerty123 on July 25, 2017, 02:51:45 PM
Haha! 55k miles or so at this point...
Title: Re: Shift lever suddenly feels lighter?
Post by: Matt Chapter on July 26, 2017, 11:52:32 AM
I had mine rebuilt around that mileage, but the symptoms were poor gas mileage and terrible grinding noises (if I remember correctly).  I also abused that gear box.  Make sure you find a pro that knows all the ins and outs of rebuilding them.  After the first rebuild on mine, it would pop out of gear because something was not shimmed or welded correctly.  The second rebuild fixed it quite nicely.

I would run it until I knew for sure something was broken - a lighter lever that is still functional seems ok to me.
Title: Re: Shift lever suddenly feels lighter?
Post by: Rob Valdez 79 R65 on July 26, 2017, 02:10:36 PM
Quote
I would run it until I knew for sure something was broken
...just keep your cell phone charged!
Title: Re: Shift lever suddenly feels lighter?
Post by: Matt Chapter on July 27, 2017, 09:59:54 AM
Quote
I would run it until I knew for sure something was broken
...just keep your cell phone charged!

Strap some walking shoes to your seat, whatever it takes!