Good morning all - Occasionally when changing down from 4th to 3rd the gear indicator lcd goes completely blank and there is no drive! Back up to 4th sorts it out and then it seems to work fine. Got a 1987 K100LT which I have only had for a couple of months so I don't know if its just my dodgy gear changes or signs of a transmission problem. Be grateful for any suggestions, regards Maenad (Nick - UK)

I`guess GPI switch or connector problem.
Here you find some reading, that would keep you occupied for a while.
And you might get some ideas about the function/problem.
(The problem in the attached link, was the connector).

Thanks Inge - will read up on it - it only happens going down from 4th to 3rd when the display goes blank and other than that the gear indicator display works perfectly. I would suspect the display but I get no drive either even though the gear selector is somewhere bewteen 4th and 3rd. The bike had been laid up for a while before I bought it.

I would guess you have a connection problem with the yellow/white wire
when the switch is at the 3 gear position.

If there is no drive, that suggests an actual gear "problem" rather than just an indicator problem.

First suggestion: Check the clutch cable free play - the manual will give the specs, but on my 1985 K100RS, there should be a gap of about 5mm at the clutch lever before there is tension on the cable.

That being loose gave me a few false neutrals when I first got my bike, and when I first test-rode the bike my girlfriend ended up buying, the gap was about 8mm before I noticed the problem and it got me stuck in a gear and not able to shift out before I could pull over and fix it.

I had/have the same fault with the false neutral appearing... I stripped the gearbox down and was unable to see anything mechanical in there that caused the problem, I have stripped the whole bike down now and am starting to rebuild it. New cables will be installed throughout and of course they (including the clutch) will be set up correctly!

With any luck that will be the cause of my problems, be good to know if it cures yours as well.

Considering the age and that you have only owned the bike for a short while I would say that more than likely the clutch spline is dry and needs new lube. This causes a clutch that doesn't disengage smoothly and so causes poor shifting.
Try preloading the lever, put some light pressure on the lever before you pull the clutch in especially when down shifting.
The indicator does have a position between each gear where the LCD wont display and that is I would say what is happening.
Don't ignore the dry spline as it will only get worse and eventually in worst case tear the centre out of the clutch.

Thanks for all the advice - gearbox oil change and a cable adjustment seems to have sorted it.

ah ..the simple things ...they all need to be done ....but for a new owner this could be confusing as the effect is quite disconcerting ....

good work buddie ...and happy riding !!!

Interesting mate I have the same. I find if I do not make the change assertively enough it can find a false neutral but a strong, positive change gets third every time. Having ready theis thread I will look to resolve this as I thought it was just a quirk of the bike.

Best
Dave

These getrag gearboxes are not one that can be casually flicked through the gears like many of the japaneese bikes, you have to be assertive or miss shifts.
They sort of remind me of the old rockcrusher muncie transmissions that Chevy used in the sixties. Strong as an ox and reliable as they come but don't pussiefoot around changing gears.

As Rick G says - the gears need a bit of positive action and having only ridden the K for about 4 months now I suspect it was me not the box causing the false neutral. Anyway an oil change did no harm and no more problems so far. Great bike meet in Devon UK at the weekend, of the 400 or so that turned up, there were about a dozen old K bikes, 75, 100 and 1100s so a good few hours of tyre kicking in the sunshine.

Maenad was that Paignton that you were at at the weekend? I would have been there as well had i not been in work!

I hear that it was a pretty good weekend from friends that did go.

Sure was twincarb - Bmad festival on Paignton Green - Sunday was a great sunny day too so a great day out and the sun brought the bikes out in droves so plenty to look at both in the show and the bike park!

Sadly I was working all weekend - it's the first Paignton bike festival that I have missed in 4 years. However, lots of my riding buddies and fellow members @ www.westcountryrideouts.co.uk did manage to make it there and I have received good reports of the weekend. I have always got on well with the members of BMAD - (Bikers Make A Difference) and was really sorry that I couldn't attend this year. Hopefully BMAD will run another "rally" this year and it will be drier than last year's event ! Camping in the middle of a permanent Dartmoor rain cloud with sideways rain was somewhat challenging and way too much time/money was spent in the host pub over the course of the weekend as a result

Hello everyone! Not had a bike for 25yrs (last one was a GPZ900R) and now own a K100RS. I was a bit nervous as I got on it, but am beginging to find what I thought I had lost a long time ago! It would seem however I have the same problem with gear shifting as has been mentioned here (plus there seems to be a 'grabby' 'clunky' sound coming from the gear box when I release the clutch - I tried doing this in rapid succession (to the biting point) to clarify the noise). I've read the comments, so pretty much know what to do (I think - unless of course it's something much more...lets say.....expensive!), but no-one has said what oil I should use. So, the question is, er.....what oil should I use in the gear box and how much of it? Thanks in advance Terry!

maybe you could check the thread " so you just bought a k bike ....now what ?" all the recomendations for servicing ...oils and much more is there ...on the "portal page"

Hi Terry
You really should put a post in the intro section and do tell what sort of RS you have so it helps with the help. If you do that our esteemed admin guy (crazy frog) will give you access to a wealth of info for download.
I use 80-90 mineral gear oil and all works fine as for filling the OEM tool kit has a special tool to measure. With a 16v engine the tool kit will have an L shaped thingy with marks and an 8v will use the shock adjust C spanner.
The measurements are 116max-126min below the top of the filler hole of the gearbox. Just use a piece of small dowel and mark it but dont use anything made of metal just in case you drop it into the box.
The K series getrag gearboxes are noisy & clunky. You need to be assertive with the change you can't just casually flick through the gears because you will miss shifts. Changing down a bit of preload on the lever helps and won't hurt.
I have a gearbox that crunches bangs grinds and whines and has done 300000km without any appreciable signs of wear.
Doing a spline lube should be on the list of to do things and a well lubed input spline will give better shifting because of smoother clutch operation.

As Chazza mentioned there's a wealth of important info within the 'What now?' page and also in the download page after you've introduced yourveryownbadself to us mob.

Be sure the gear oil you use is rated Hypoid & GL5 and use 850cc +/- 50cc, of 80W90 or similar viscosity and you'll be golden - the same applies for type and weight in the final drive, though fill to spec of 260cc if it's not a Paralever final drive (Paralevers are only on 16V).

In addition, though it's a several hour task on a lazy Sunday arvo, lube them splines (all three) if you don't know when it was done last. Compared to your GPZ900 with its wet clutch the K's clutch is bolted to a relatively heavy flywheel thingy and is, as you likely already know, a dry set-up much like a car.

As Rick suggests, a positive effort (a toe on the lever to preload it) produces a rewarding shift. A mastery of such things is all part of the satisfaction of owning one.

Thanks guys, mucho appreciated. Will (also) go to the intro pages and say hello formerly, sorry about that, I just saw 'false neutral' and started reading. Thanks again. Terry The Dactyl.