john fox Posted October 2, 2007 Share Posted October 2, 2007 Hi all I have a gearbox which allegedly has been rebuilt by an ex REME VM but when changing up from 2 to 3 it will not engage first time and it is necessary to hit to pedal a second time before it engages, once in there is no slippage or any other form of problem. Changing down from 3 to 2 is fine and works first time. All other gears engage smoothly and work fine. Whats wrong with 2nd :dunno: Suggestions to date are: a) the linkage from the pedal to the box was incorrectly set and needs to be readjusted - is this possible? I would have thought that if the linkage was the wrong length then it would affect both going up and down on the gear (and more than just one gear?) b) the 3rd gear "finger" inside the box may have a burr or wear which stops it engaging on the busbar correctly. I am assured by the VM that he set the busbar height correctly using the dipstick gauge. I guess I would favour option b as when changing down the "finger" simply slides off the busbar and therefore would apply when going up since it has to lift over the busbar to engage. Any suggestions before I have to take the box out are gratefully received. If option b) applies can it be done in situ? Cheers John Quote Link to comment Share on other sites More sharing options...
MiketheBike Posted October 2, 2007 Share Posted October 2, 2007 John, can't you just take the cover off and see if its all operating smoothly? I think just taking the cover off the gearbox gives you acess to the busbar etc? Mick Quote Link to comment Share on other sites More sharing options...
sirhc Posted October 2, 2007 Share Posted October 2, 2007 John, As Mick suggests you can remove the covers and have a look at what's going on inside. It's easy enough to remove the cover which contains the selector mechanism. Check this for a weak spring or anything else which looks or feels wrong. You can actually get someone to press the pedal while you select the gears manually and check that everything works as it should. We spent quite a bit of time adjusting linkages on our Fox in order to get all 5 gears to select smoothly. Remember there may be a problem with either the gear change pedal or the selector linkage. Chris Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted October 2, 2007 Share Posted October 2, 2007 I have a gearbox which allegedly has been rebuilt by an ex REME VM but when changing up from 2 to 3 it will not engage first time and it is necessary to hit to pedal a second time before it engages, once in there is no slippage or any other form of problem. Changing down from 3 to 2 is fine and works first time. All other gears engage smoothly and work fine. Whats wrong with 2nd :dunno: John, I would say that it is all down to adjustment. You say the box has been rebuilt and adjusted to correct Bus Bar heights. This may have been so, but if it had been fitted with new bands, they are now bedding in and it could be that the auto adjuster is not touching the peg. You need to remove the top cover and select the gears and use the gear change pedal to observe if the adjuster is in operation. The Bus Bar heights may have to be reset. It sounds like this is why the gear will not engage. Also the linkage from pedal to box needs checking for correct adjustment, this needs to be done in 1st gear as that is the one with least freeplay. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.