Go Back   Horizons Unlimited - The HUBB > Technical, Bike forums > BMW Tech

BMW Tech BMW Tech Forum - For Questions specific and of interest to BMW riders only. Questions comparing which bike is best etc go in the "Which Bike" forum.
Contact Overland Solutions for all your custom modifications and setup for overland travel.

7 Litre Camel Tank Lets You Explore More, Click to Find out More!

LinkBack Thread Tools Display Modes
Old 17 Feb 2009
Registered Users
HUBB regular
Join Date: May 2008
Location: London, England
Posts: 43
R100GS gearbox endfloat

Just finished rebuilding the gearbox on my 1992 R100GSPD, new bearings/seals plus HPN lower 1st and higher 5th.

The closest l could get the endfloat on the three shafts was 0.08/0.12/0.15mm after many attempts and pulling my hair out trying to get around 0.05mm the bike runs fine with no nosies and gear changes are smooth would this excess clearance cause any issues or serousily shorten the life of the gearbox?
Morocco 2012
Morocco 2010
Reply With Quote
Old 17 Feb 2009
FUTURE's Avatar
Contributing Member
HUBB regular
Join Date: Jun 2008
Location: Back from visiting Uncle Ho
Posts: 92
Really dumb question rleated to the topic. What is end float??? I have never heard of this till I bought a BMW myself and still don't understand what it is...
Reply With Quote
Old 17 Feb 2009
Registered Users
HUBB regular
Join Date: Nov 2007
Location: Ireland
Posts: 24
My understanding of endfloat and the need to measure it is this- when you put the shaft and bearing back in the housing ( i.e. when you put the box back together)there will be a small gap between the bearing and the housing, if left as a gap the bearing can try to move into that gap when under load and put a strain on the bearing in a sideways motion thus damaging the bearing. A shim is a small piece of metal shaped like a disk which is used to fill that gap and thus preveent the bearing from makming that very undesirable movement. Only problem is that you don't see that gap as it is only until after assembly that the gap exists and then it is inside your gearbox invisible to yourself, so you have to estiumate it using a precisely measured plate which bolts on in place of the housing. This plate has holes going right throough it to accomodate the bearings, by using the measured thickness of the plate and by measuring how far beyond the plate the bearings will extend it is possible to ascertain what thickness of a shim you will need to fill the gap between the bearing and the housing in your final assembly.

Thats my understanding of it, I may be wrong as I am no expert and have never actually carried out this procedure.
Reply With Quote
Old 18 Feb 2009
FUTURE's Avatar
Contributing Member
HUBB regular
Join Date: Jun 2008
Location: Back from visiting Uncle Ho
Posts: 92
Ok... I think... Thanks for that.... My gearbox was overhauled just before i bought the bike so hopefully I wont need to check any of this fro some time to come.
Reply With Quote
Old 18 Feb 2009
Registered Users
Veteran HUBBer
Join Date: Oct 2002
Location: Stockholm - Sweden
Posts: 316
Do you have the propper tools?...

There is just about no way less you have the BMW plate for axial play adjustment... Red-neck plates can be made from gearbox rear-end-covers.
Motorworks in England used to sell such - perhaps they still do.

IF you get the play too tight... you will need a new gearboxhouse...

If too loose is not as bad though, but wear will be more rappid....

IF one of the bearings breaks... the gearbox can litterally explode... Oak Oshlen have written about this, and an aquaintance of mine have experienced it first hand. When it explode it can rip off the lower leg on the side it bursts on.
Drive Safely,
Reply With Quote
Old 20 Feb 2009
Registered Users
Veteran HUBBer
Join Date: Jun 2005
Location: Cape Town / South Africa
Posts: 223
Better too loose than too tight.
A setting of 0.05mm is not really possible but to get the measurement between 0.05 and 0.1 is what you ideally should achieve. If the box is back together and the biggest gap is not more than 0.15mm I would leave it. A larger gap will most probably have a bigger influence on the shifting quality than bearing wear as the shafts can now migrate more freely forward and back.
Have you added the gasket thickness in your calculation?
I have found gearboxes with the end-float of over 0.3mm with no obvious damage caused by this but if even just slightly preloaded the bearings will start to wear excessive within the first 1000km.

Exploding gearboxes is not that dramatic but it does wreck havoc with the insides, shafts and gears, and almost always damages the gearbox cover. Repairs can be astronomical, so it is safer to have the gearbox overhauled before this appears. Check for metal filings on the magnetic pickup on the sump plug. Fine fibers that leaves your fingers dark grey and feels silky when you rub it between your fingers is normal but if you see and feel shiny flakes when rubbing the material on the magnetic plug between your fingers you can be assured that a bearing is on its way and it will be safe to say you should have it attended to in the near future.
You can also get a clear indication by turning the back wheel when on the centre stand and the motor switched of. A nasty rumbling noise that progressively gets worse when checked regularly is also a sure sign that the bearings is busy failing. Just make sure this rumbling is not part of the final drive which will mean you might have to service that instead.
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 Registered Users and/or Members and 1 guests)
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
2KF gearbox Guy Scheveneels Yamaha Tech 3 24 Feb 2012 07:53
2KF gearbox Guy Scheveneels Yamaha Tech 2 24 Sep 2007 21:32
KLR 650 gearbox - HELP! IanElsley Kawasaki 6 26 Mar 2007 12:47
XL/XR gearbox Stuart Jenkins Honda Tech 0 20 Aug 2004 00:34


HU DVD Summer Special!

Now that summer is here, get On the Road! Take 30% off the Achievable Dream - On the Road! 2-DVD set until August 31 only. Get On the Road! Learn the tips to staying healthy, happy and secure on your motorcycle adventure!

Our veteran travellers share their tips (and great stories) for staying healthy, happy and secure on your motorcycle adventure.

"A fantastic, informative and inspirational DVD."

"It's brilliant - thank you very much!"

Check it out at the HU Store! Remember to use Coupon Code 'ONTHEROAD' on your order when you checkout.

Renedian Adventures

Renedian Adventures

What others say about HU...

"I just wanted to say thanks for doing this and sharing so much with the rest of us." Dave, USA

"Your website is a mecca of valuable information and the DVD series is informative, entertaining, and inspiring! The new look of the website is very impressive, updated and catchy. Thank you so very much!" Jennifer, Canada

"...Great site. Keep up the good work." Murray and Carmen, Australia

"We just finished a 7 month 22,000+ mile scouting trip from Alaska to the bottom of Chile and I can't tell you how many times we referred to your site for help. From how to adjust your valves, to where to stay in the back country of Peru. Horizons Unlimited was a key player in our success. Motorcycle enthusiasts from around the world are in debt to your services." Alaska Riders

contest pic

10th Annual HU Travellers Photo Contest is on now! This is an opportunity for YOU to show us your best photos and win prizes!

NEW! HU 2014 Adventure Travel T-shirts! are now available in several colors! Be the first kid on your block to have them! New lower prices on synths!

HU 2014 T-shirts now in!

Check out the new Gildan Performance cotton-feel t-shirt - 100% poly, feels like soft cotton!

What turns you on to motorcycle travel?

Global Rescue, WORLDwide evacuation services for EVERYONE

Global Rescue is the premier provider of medical, security and evacuation services worldwide and is the only company that will come to you, wherever you are, and evacuate you to your home hospital of choice. Additionally, Global Rescue places no restrictions on country of citizenship - all nationalities are eligible to sign-up!

New to Horizons Unlimited?

New to motorcycle travelling? New to the HU site? Confused? Too many options? It's really very simple - just 4 easy steps!

Horizons Unlimited was founded in 1997 by Grant and Susan Johnson following their journey around the world on a BMW R80 G/S motorcycle.

Susan and Grant Johnson Read more about Grant & Susan's story

Membership - help keep us going!

Horizons Unlimited is not a big multi-national company, just two people who love motorcycle travel and have grown what started as a hobby in 1997 into a full time job (usually 8-10 hours per day and 7 days a week) and a labour of love. To keep it going and a roof over our heads, we run events (22 this year!); we sell inspirational and informative DVDs; we have a few selected advertisers; and we make a small amount from memberships.

You don't have to be a Member to come to an HU meeting, access the website, the HUBB or to receive the e-zine. What you get for your membership contribution is our sincere gratitude, good karma and knowing that you're helping to keep the motorcycle travel dream alive. Contributing Members and Gold Members do get additional features on the HUBB. Here's a list of all the Member benefits on the HUBB.

Books & DVDs


All the best travel books and videos listed and often reviewed on HU's famous Books page. Check it out and get great travel books from all over the world.

Motorcycle Express for shipping and insurance!

Motorcycle Express

MC Air Shipping, (uncrated) USA / Canada / Europe and other areas. Be sure to say "Horizons Unlimited" to get your $25 discount on Shipping!
Insurance - see: For foreigners traveling in US and Canada and for Americans and Canadians traveling in other countries, then mail it to MC Express and get your HU $15 discount!

All times are GMT +1. The time now is 12:52.