gearbox problem r100gs

[seancb]

Hi all

hope some one can help my r100gs has got stuck in 1st gear cant get in to nutal or any other gears. was riding home last night put it in to gear moved of then would not got up or out of 1st then had to push the bike home any help or ideas would be great.
Sean

 

[Voyager]

Hi all

hope some one can help my r100gs has got stuck in 1st gear cant get in to nutal or any other gears. was riding home last night put it in to gear moved of then would not got up or out of 1st then had to push the bike home any help or ideas would be great.
Sean

It sounds as though the gear selector pawl spring has broken - you are probably finding that the gear lever doesn't return to the central position by itself.

I have had a look through my photos but I don't have a clear one that shows the components. I have a spare box in bits and could strip and photograph the selector mechanism components if you like.

I'm afraid its a gearbox out and strip-down job . . all for a £1.26 spring.

(Rumour has it that it is possible to invert the bike and then select third gear (because the selector pawl drops into the camplate when upside down) - its then possible to get home in third ).

Bob.

 

[(RIP) Proff]

Hi all

hope some one can help my r100gs has got stuck in 1st gear cant get in to nutal or any other gears. was riding home last night put it in to gear moved of then would not got up or out of 1st then had to push the bike home any help or ideas would be great.
Sean

Paging Rob Farmer or Steptoe to the Airhead Forum please !!!!
they'll tell you exactly what it is !!

 

[Steptoe]

Check the no cost option before removing and disassembling the box.

Check that the gear lever selector shaft nut is tight ( the shaft that goes into the gearbox), the bolt can work loose and give the same symptoms as a broken detent spring.

It is still possible to change gear with a broken detent spring. You just have to turn the bike upside down Don't laugh, very worthwhile knowing if you happen to be stuck in 5th in the middle of a desert, or stuck in 1st with a long ride in front of you.
That way you can get it into 3rd or 4th, or whatever gear suits the occasion to get you home.

 

[Steptoe]

I have had a look through my photos but I don't have a clear one that shows the components.

Here's a thread showing all the [URL="http://www.ukgser.com/forums/showthread.php?t=35961&highlight=steptoe"]PARTS[/URL]

 

[seancb]

thanks for the info
the shaft bolt is fine
could be the spring but the other problem is you cant start the bike when it is in gear

Sean

 

[Voyager]

thanks for the info
but the other problem is you cant start the bike when it is in gear

Sean

That sounds like a completely different problem as it should start with the clutch lever pulled in.

If you connect the neutral light leads together so that the neutral light is on it will think its in neutral. It should then start (but de-clutch it first ).

Bob.

 

[Steptoe]

the other problem is you cant start the bike when it is in gear

Sean

Unplug the clutch starter bypass switch ( follow it from the clutch lever where it plugs into the loom just under the front of the tank), bridge the plug and it'll start.

Be careful as it will now start in any gear, so always pull the clutch in to be on the safe side.

 

[seancb]

thanks

will try that soon and see if it will start Sean

 

[seancb]

hi all

if i got to replace the release spring is there any other seals that what be good idea to replace at the same time

Thanks Sean

 

[Voyager]

hi all

if i got to replace the release spring is there any other seals that what be good idea to replace at the same time

Thanks Sean

Probably as well to do a few things while you're in there . . . .

Input shaft seal.
Output shaft flange seal.
Gear lever shaft seal.
Clutch push rod seal (a small thing that goes at the rear of the input shaft).
All three selector mechanism springs (there is a school of thought that says "leave well alone if they aren't broken").
Front and rear output shaft bearings.
The nylon indexing roller (I replaced mine with a SKF bearing, but it seems to have made gear selection a bit sticky).

Good luck - post us some photos

Bob.

 

[Solo Lobo]

The nylon indexing roller (I replaced mine with a SKF bearing, but it seems to have made gear selection a bit sticky.

I just had the box on my '81 G/S rebuilt and the shop used a K-bike roller in place of the nylon roller and am having the same sticky shifting issue... I am told it gets better with use. Fingers crossed.

 

[Kenny]

Might be worth just simply taking the gearbox out and fitting a reconditioned one from one of the advertisers listed at the top of the webpage.....saves an AWFUL lot of hassle..and comes with a warranty. These gearboxes arn't the easiest of items to repair yourself and can end up taking ages if you forget to order a simple item during the re-build etc etc

 

[seancb]

Thanks for that still looking for ideas and does any one have any ideas on how to get the bike back to the uk as i have EU no brake down cover?
Sean

 

[Voyager]

Thanks for that still looking for ideas and does any one have any ideas on how to get the bike back to the uk as i have EU no brake down cover?
Sean

In your PM you said that you were working in France; how much longer will you be there ?

Just thinking that it might be easier/cheaper to send the box home for repair then ride the bike back.

PM me if you want me to do the job.

(cost = parts and postage).

Bob.

 

[seancb]

hi all

I my have got a solution for the gearbox which is that I have part of a r100/7 and my put the gearbox in the r100gs. does any one now if the gearbox will fit and work fine thanks Sean

 

[shafted]

The gearbox should fit okay, just check the input spline's are okay.
Safe riding Karl.

 

[Kenny]

Yup +1 on that...gearing will be a tad haywire but definately enough to get you home !! The drive shaft to gearbox flange bolts are the stretch type ( and the OE toolkit 10mm ringed spanner is the best for removing them ) so if using them again to get you home...a little Loctite on them wouldn't go amiss !!

 

[Rob Farmer]

When my 100/7 destroyed it's gearbox I used an 82 box as a doner. The input shaft is longer on the 100/7 so you will need to change that to allow the clutch to operate. you will also need to change the output end cover so that the correct length push rod can be used.

It's not quite as simple as simply swapping the input shafts because the 100/7 gearbox uses input gears with a 15° angle (17.5↑8) on the later gearboxes. The later gearbox also uses thicker gears. The only solution is to swap all the gearbox components over. Which ever way you do it the gearboxe need rebuilding.

Take Voyager up on his kind offer

 

[Voyager]

I just spoke to Sean's mother (who has the 100/7 in her garage).

She can't find the number plate, but thinks its a 1974/75 bike.

This would be from the heavy flywheel engine with different gearbox splines to the 100GS.

All in all, taking in Rob Farmers comments above, it sounds like a no-no option.

We are working on a plan to get my spare box to Sean in France.

Are there any 'Tossers' near Beziers who could help him swap the boxes over (he hasn't done this before) ? ? ? ?

Sean will be in France until end-August '08.

Bob.