Gearbox advise please

Riz Sauvage

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I trawled through the site one night before getting my current 1100, and came upon a few threads relating to gearbox troubles on the early 1100's, but I'm buggered if I can find them now.

Could someone give me a few (usefull, & relevant) tips please... :)
(The "don't eat yellow snow" one I've heard already thanks)

I have a 1996 1100, the gearbox rattles, (bit like a loud tappet) and skips/jumps under acceleration in 3rd.

What needs rebuilding to cure this, and which later model gearboxes are compatible for an upgrade?
Thanks in antisipppppppation..
Si
 
I did the same research before I bought my '94 1100.

The pre '97 gearboxes are known for problems which stem from the type of bearings used on the input and output shafts. This can lead to excessive movement of the shafts which in turn leads to poor engagement of the shift dogs which in turn leads to wear of the shift forks as it skips out of gear end then bounces off the shift fork, back into engagement (the 'skipping' you feel). This often seems to manifest in third gear - I don't think there's any particular weakness with third - it's probably just that third sees a lot of use (it's certainly 'the gear' on my bike :) ). There is a (believable) theory that the problem is actually caused by poor assembly at the factory (failure to shim the shafts properly), as some gearboxes are fine and go round the clock with no problems, but some get 'the problem' early in their life.

Thus far, my gearbox is fine although my first gearbox oil change (only had the bike a few months) did produce quite dark oil (can indicate seal failure in gearbox bearings). I guess I'll see what happens as time progresses ;)

In terms of rebuilding early boxes - apparently it's possible to bring an early box up to almost '97 spec (apart from one bearing which shouldn't ever be a problem anyway). As Jaythro says, Anton's site has a load of information about these gearboxes. I'm not sure exactly which parts are changed to do the 'upgrade', but Anton seems a pretty helpful guy and I'm sure he would tell you if you asked him (you can get hold of him on Adventure Rider) - if you find out let me know!

If / when mine finally needs attention I think I'll probably just bite the bullet and give to Scriminger to sort out (by all accounts they do excellent work on BM transmissions) - but you never know, I might give it a go (just the shimming seems a bit tricky without special tools).

cheers
Matt
 
Thanks very much to everyone for their input, the advice/help is much appreciated.
Kind regards,
Si
 
R1100g/box

Gearboxes before 1998 are suspect .I have a 1996 R!!))RT .First box started skipping 3rd and 5th ears at 27K.Unfortunately got so called recon box from motorshirks lasted 13 months and 7K miles!Went o SCRIMINGERS who rebuilt the box and "dovetailed the 3rd and 5th gears.Trouble with early boxes is 3rd and 5th gears have low and high dogs and after while they slip over the low dog and connect with the high dog , shut throtle and reverse happens.Ring steve at scrimmingers.I did 75k on K75 ,perfect box yet same year 1996? Good luck! Chris
 
The pre 1997 (hence M97) boxes could suffer from incorrectly shimmed taper bearings and/or selector wear caused by the under-sized dogs allowing the gear to slip out, usually in third. I always make sure the gears engage properly by holding the gear lever up until the clutch is fully home. I also use decent fully synthetic oil (75/140) GL5 in the gearbox; the change is much sweeter and it doesn't deteriorate when hot like it used to when I put 80/90 in it. So far, so good............. When it does go, as I'm sure it will, I'll take it the Steve Scriminger and have it uprated as nearly as possible to M97 spec.
 
Gearboxes before 1998 are suspect .I have a 1996 R!!))RT .First box started skipping 3rd and 5th ears at 27K.Unfortunately got so called recon box from motorshirks lasted 13 months and 7K miles!Went o SCRIMINGERS who rebuilt the box and "dovetailed the 3rd and 5th gears.Trouble with early boxes is 3rd and 5th gears have low and high dogs and after while they slip over the low dog and connect with the high dog , shut throtle and reverse happens.Ring steve at scrimmingers.I did 75k on K75 ,perfect box yet same year 1996? Good luck! Chris

they changed in autumn 96 to the M97 box, I had a 96 R1100RT that was fitted with the M97 box from new, I now have a 1999 R1100RT, yours needs serious work, but you could keep the costs down by removing and fitting yourself, or more, some of the people on here have repaired and modified their own box :thumb2
 
My m95 box on my 1995 1100 GS was jumpin out of gear in 3rd. Arse:(
got a cheap m99 box :thumb, fitted it works fine, done 7000 miles since refit.

Or ye can have a refurb box from a guy near Sheffield who dose a good deal.

A few members on here have used him
pm me for details

ugg
 
Doh :(

Just bought a 96 (P) 11GS. Loads of service history and all the old MOT's.
Last service bill stated that Paralever bearings may be required in the future and recommend replacing all trinions.

Wasn't too concerned about this because I believe I got the bike for a good price.

I now know why! (Thanks David if you're reading! What goes round comes round:thumb2)

Basically, after doing probably two hundred miles on her, I have noticed the third gear skip. It only seems apparent under load in 3rd, I have tried to replicate it in other gears but they seem okay.

Sooo, I'm frightened to ask, but what's the likely damage and who would you recommend taking it to please?

I see a couple of names in this forum, obviously I know of Steptoe but who and where are Scrimingers? Are they BMW specialists or just gearbox specialists?

Can you ride around the issue or will it just develop into a bigger more expensive issue affecting the other gears if left?

Finally, are the paralever bearings and trinions expensive to replace?

Many thanks for any help guys.

Skid :thumb
 
Paralever bearings and pinions (not sure what trinions are?) are cheap and easy - £30 for the bearings, pinions (if you need them) about £20 a side.

Third gear skip - Sciminger or Steptoe.
 
Thanks guys for the responses.

You'll have to excuse my typing, it's been a long day. :blast

I actually copied the spelling off of the service receipt but thought it should have read Trunions, whatever the hell they are????????????

Not worried about the cost of that though, more the gearbox issue.

I'll get on the phone in the morning for some quotes (When the missus isn't in earshot) :hide
 
Just a note that folks have been known to run them for many thousand miles, with the third gear skip :augie

Thanks for that.
This was one of my major concerns. I don't mind short shifting and utilising the accerelation in the other gears If I continued to use it as is for now.

BUT....

would it cause further more expensive damage by doing so and potentially have a serious failure which could result in a lock up and spit me off?
 


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