john b Posted July 7, 2009 Report Share Posted July 7, 2009 I have a Montesa 172 which is just about finished in terms of a rebuild, with a fair bit of money spent on it. It's very very original and a lovely bike. The problem is gear selection. When I bought the bike it would go in and out of first OK, but into second and above was very notchy. With the engine, all I've gone is a top end freshen up (it's still on original bore), but now it's all back together there is a problem with gear selection. I've tried everything I can (and I'm resonably mechanically minded) but it will not go into second or above. Clutch operation is also very very heavy. Im sure to solve both of these is very simple for someone who knows older Montesa engines, but I'm at a loss !!!! What I was after was is there anyone out there (preferably in the North East) who can have a look at it, or recommend someone to have a look at it. Any help on this would be very much appreciated - I don't want it doing for nothing, but also I dont want to pay main dealer prices ! Yours hopefully ......................!!! cheers John Quote Link to comment Share on other sites More sharing options...
vintagecota Posted July 7, 2009 Report Share Posted July 7, 2009 First you need to take off the right side cover and inspect the shift mechanism. Check the rack and pinion for sloppiness, worn teeth, missing teeth, etc... Then go into the shifter drum, under that cast iron circle with 3 screws. It's possible to install the pawls incorrectly, and check the teeth on the pawls for wear. Failing that, you'll need to split the cases to check for bent forks... While you have the cover off, remove the clutch basket and take out 3 of the 6 springs. This will lighten the clutch noticeably and still have enough bite to work the bike. The clutch might slip a bit in higher gears, like on a road, booting up a hill, but should be fine in the sections. If you have the Clymer book it shows the shifter stuff and how to correctly assemble it. Quote Link to comment Share on other sites More sharing options...
woodbutcher Posted July 7, 2009 Report Share Posted July 7, 2009 I HAVE OLD CLYMER MONTESA MANUAL YOU CAN BORROW LIVE NEAR METRO CENTRE . 07984 955797 STEVE . Quote Link to comment Share on other sites More sharing options...
belldane Posted July 8, 2009 Report Share Posted July 8, 2009 Hi I was going to suggest a site to get the Clymer Manual but for copyright problems it is no longer accessible. Apart from the things Vintage Cota has suggested you may also want to try taking the shifter detent bolt (left hand side towards the back of engine) out to see if the spring has been stretched at some stage to make gears not slip out. There is a spring and a small ball bearing which can be taken out with a magnet. Decrease the amount of tension on the spring and see how it goes. It is a long shot but may be worth a try. Failing that do as the old fella says. I have owned a couple of 172's and some problems appeared to be broken kick starter shafts and then broken side case where the starter shaft stopper hit the case, so if you come accross any 172 motors that are still intact, buy them. I have a bottom end here under the house which was fine until I broke the side case. Hope this helps. See ya Quote Link to comment Share on other sites More sharing options...
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