Not trying to spend your money for you, but did you try AJG and see if they can help you out? Google "AJG Twinshock" and you'll find 'em on FaceTube (whatever), as the link evidently isn't allowed here. Trick stuff there....
I suspect that the mountings of the two engines will be slightly different. You need a Montesa expert, I am not, but it does seem to me that you may well be going about sorting the rear wheel clearance the wrong way. Of course if you are not bothered about originality then crack on. If the wheel is moved as far back as possible does this improve the clearance issue, if so some longer rear wheel mounting lugs could be the answer. You can obtain these from a number of trials parts shops, or make them your self...not too difficult. This might slow the steering a tad but if it lets you keep the wider tyre all well and good. Is the narrower rear tyre unsuitable for your riding style, a narrower tyre will let a bit more power out if you get my drift. ?
Thanks for your thoughts section swept
On the 123 cota it when new it came running 20" front and 17" rear , which seems to be near impossible to find, certainly in the uk................(same as 172 cota swing arm, which would allow and give room for 18" tyre/rim.
Wheel, at present is right back in s/arm, as per your idea, but tyre (at present am running 400x18) still rubs on chain guard, and very close to swing arm pivot.
My other thought is going down to a3.50 x18 section tyre, (only found one distributor of these in uk) which will give slightly more clearance
Anyone know if the motor of early 123/172 cota (red one) will fit into later 200 frame ?
Am running a 123 with 400x18 rear tyre, and clearance in swing area isn't good to all.........easiest way would be to find a 172 swing arm, but they seem like hens teeth in the uk
I'm aware exhaust/silencer is different on the 200 cota
Can anyone give me an idea if an early cota 123 engine will fit into a later cota 200 frame........( and all 123 ancillaries swap over), although I realise exhaust/silencer is different)
Reason for asking is at present running 123 with 400x18 rear tyre, which is rubbing, (still using 123 swing arm, as not been able to find a 172 arm)..and the '200', I believe was the later version of the 172 with the wider swing arm.
The original size tires for the 123 are still available. Google clasicaslegendarias or Motos del Abuelo. They both have the tires listed on their catalogues but you would have to enquire as to availability . I have bought parts from the latter and had no problem.
Thanks cota172, I did a uk based internet search, and nothing came up, which I based my earlier answer on; Hmm, unless keeping to standard spec, still prefer to stay 21" front and 18" rear, myself.
Hi Andy, a bit late to the party but hey, so what.
I've the same bike, a 247C (Competition) and they are lovely bikes, light, small with a very friendly and smooth engine.
The early ones from June 1978 had front fork spring air assist whereby you could pump a little air into the front end to firm them up. This feature was soon deleted though, as they couldn't get the air to remain in the forks.....sounds familiar to modern MX boys
Mine is heading for a rebuild in week or so, only for a frame repaint as the tank paintwork is still original and they are only original once.
PS Your air filter is correct.
Thanks iconic558, thankfully the 247 seems to be ok, at the mo...........just as well really as the 123/172 is in the process of being fettled, - and under engine protection being added (clutch arm is under engine, and quite exposed)
Yes, as far as I know the original size tyres are no longer available, so only option, really; Even finding 3.50x18 trials tyres isn't easy, certainly non of the major tyre makers list them, and whilst I know the 172 cota shared its frame with the 123 cota, the swinging arm must be different, as 172 ran 400x18 tyre, which wouldn't have rubbed, like it does on my 123.
Cheers.... look like they’re worth a punt. All dry and dusty here... but no stranger to the saddle soap or the dubbin. Was looking at pics, reviews and a video on revzilla... looked like a decent boot.
One big + for me, although not found I need it, is they also do a 'waterproof insert'..........which, on a multi day WET trial might be a bonus. (as I say, my feet have remained dry all the times I've worn mine, and that has involved scrabbling about in stream beds, when I've dropped montesa.....)
Having brought a rider back to life after he suffered a (suspected) heart attack, whilst on an isolated Byway, a few years ago, whilst I can appreciate, and laugh at the above scenario, its just amazing just how much you remember - when faced with summat like that, yes, quite a while previously to that incident,.. I had attended a basic first aid course....in the days when it was 'breath of life and chest compressions'. (And in the days before mobile phones were as available as they are now)
Think the Op was right to raise this subject............and I think its generated a healthy (pardon the pun) conversation.
a - most tech data sheets will say something like no tubeless tyre is designed to go below 6 psi (and not risk the chance of rim failure) - now that's not how we all use them but that's what the small print says ...
b - all proper trials tyres are 400x18, except the x lights (made in metric @ 120/100/18). you should be able to get trial pattern tyres from mitas, cheng shin and maybe some others but they won't be a trials like (compound, etc) as the rest
Hi Rabie, the tubless issue would not be a problem, as I run tubes;
YOU are looking for problems that are very rare ,next you,ll want a ambulance at a trial just incase . You would find any trained first -aiders would step up if needed .As for clubs, clubs are run by volunteers who is going to take responsibility & liability( blame clam society) if the first aid treatment goes wrong ?,Read the sign "caution motor-sport is dangerous" so is it not down to the rider for his/her own safety ? seen loads drinks bottles taped to bikes never seen a first aid kit . Should we put entry fees up and book a ambulance for every trial first aid will be well covered then or just use 999 as we do now" that worked for me !"
I don't think OP was suggesting going the Ambulance route, etc, just that if there war any first aid trained riders/ observers in attendance, they be identifiable; By the very nature of accidents, any Fiist Aid, administered 'on site' is just that.........First Aid;
Regarding liability........it would be a pretty poor day if the person trying to help someone in trouble (of whatever kind) stood back and worried about any repercussions.......(and here I'm speaking as a First Aid trained person)
Another point here,.........whilst yes in an ideal world, 999 is last resort, in some area's of the country, any sort of phone reception is hit and miss.
Can understand your reasoning, On It, for your post, as well.............tis an interesting topic, maybe's as Trials 'like some other sports', is moving forward, and sections are by the very nature of the machinery being ridden, now, are getting more technical, the OP's raised question does have some relevance.
Whilst on the subject of decent Trials tyres, I'm looking for a 3.50x18 (no idea what that converts to in new sizing).............Have found one on ebay, not a known make a far as I know, and I guess at a push it will do the job, - but ?
Cannot go 400x18 as it rubs on swing arm
Bike is a 70's 123 cota, which originally had 17" rear wheel............
Reading with interest this thread, after spectating at Highland Classic this year,.........looking to enter next, and coming from a county not noted for rocky going (southern England), am looking to fit external bashplate to my 123 cota......extended to cover underslung clutch arm.,..also moving footrests back n down slightly, so thanks for pic's Wobbler.
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70's cota 123 into later cota 200 frame
in Montesa
Posted
Think your safe, there.......spoken with him, and he's not done anything for Montesa........yet.