belldane

Hey Common guys and girls Think about how many times those bikes have won competitions without electronic stuff. If you have a problem riding them with the bare essentials get out of twin shock. Leave it the way it is. My is fine the way it is. My 348 and 2 247's have not missed a bit in over 20 years. Think about it and the cost and the problems you may have are just not worth it. See ya

OK Bluey I am back mate. You seem like a determined little bugger so go for it. Will do you an email soon. See ya mate

If you have a lot of time on your hands by all means try the Mikuni. I have a a couple of 247's with the same carb as yours and a 348 which I tried to fit a Mikuni to as it just was not running properly. In the end I just gave up, jetting just was not right, great down low or up the creek up high or vice a versa. In the up and ended buying a spare 348T for parts and swapped the carb over. Problem solved. It ran really well but had the original carb re-sleeved anyway by a bloke near Sydney and all my problems are over. I know the 348's have a different carb. Is there any one you know with a 247 with a carb the same as yours ? That would save you a lot of time and expense. One thing that does come to mind which I should have mentioned earlier is whether you have checked that bakelite spacer between the carb and the cylinder. If it has a slight crack it can cause all of the symptoms you are experiencing. I have a mate in England whom I met through this forum and he was having the same problems as you. I posted a spare spacer I had here and he as happy as Larry. Bike starts first or second kick all the time and no stalling any more. He did tell me that the only way he could get it to go when it stopped was to take the plug out and do the old a bit of petrol down the plughole routine. I reckon the problem is something really simple after all there is not much that can go wrong with those motors and you seem to have covered nearly everything. You can PM me if you like but I am off to Canberra in the morning and have no idea when I will get back. Manuel

That little brass plunger is the right one to use. However it can fit into that little slot that actuates the clutch either way. Only one way to fit it as the bottom sides of that plunger have different cutouts. Can't remember which way it goes now but I can check if you want. I have always used 10w 30 oil on the clutch side with no problems. As far as building up that plunger with a dob of weld, It may work for now but I would think that it is eventually going to wear the three pronged thing that it rests against and then you will be up for some new parts.

What sort of carb is on the bike? No doubt the old tickle me until I drop fuel all over the engine covers sort. If it is that sort the carb could be worn out. The slide and the carb were made out of the same material and after much use they were stuffed. Do you have anyone in your area with a similar bike ? If you do and their bike is running properly swap carbs and see what happens. Whereabouts in Australia are you ?

Hi Just sitting here thinking about that idle problem. If you turn the idle screw up so that it is idling higher then it should be, does the motor stall ? If it doesn't the problem could be that the slot on the slide where the idle needle goes into has worn and no matter what you do can't get it right. A bit of a turn to the right and the idle is high. A bit of a turn to the left and it stops and there is no adjustment in between. Just a thought but you seem to have covered all the other things that are causing you problems. See how you go

That little key can be a *******. I usually dab a bit of glue on it and leave it overnight to set. That will stop it from sliding out when you are putting the flywheel on and having to dismantle the backing plate to retrieve it.

Finding another engine for the Cota may be a bit difficult. They do come up occasionally on Ebay but mostly they are overseas sellers and most of the time not complete. To get that broken key out get yourself a very fine hard punch and tap the key on the edge and it should pop out. As far as that spring washer is concerned I would not bother changing it. I have reused those washers on my bikes many, many times with no problems. Once you put the whole lot together make sure you tension that nut to the recommended pressure. From memory it is around 70 foot pounds. I can check if you like and get back to you

Yep. The primary gear on the clutch side will either come off very easily with a 3 jaw puller or can be very stubborn to get off. If it is stubborn you will need to put as much pressure as you can on the puller and heat the gear up with an oxy. Just watch it as it can come out at a hundred miles an hour. Apart from that the rest is fairly straight forward unless the gearbox collapses on you as you split the cases and end up with a pile of gears and rollers at the bottom of the case. Have fun

I painted the barrel and head on my 247's with that VHT stuff but left the casings in original polished alloy. I really don't know what went wrong but if I were you I would just pour some more petrol on the cases and bring them back to bare alloy.

Ok Vintage I stand corrected but it has been a while since tinkered around with the 172 motor. Nice bike to ride it was until it was stolen about 7 years ago Manuel

The 172's did not have the pawl set up as other Montys. The gear lever is connected to a shaft that goes though both cases and from memory there are a set of teeth that obviously engage to another set of teeth to make changing gears possible. I have a 172 motor under my bench and I can have a look if you like but I think your problem may be those teeth not engaging properly or an internal problem and you will need to split the cases. Vintage Cota. What do you reckon ? Hope this helps Manuel

No worries mate. Glad to help out. Manuel

Hi think David is right but do you have an engine number as it could also be a 349 motor. Apart from the internals it is a very similar motor to the 348

I got some rings a couple of years ago for my 348 from Jared Bates at southwestmontesa.com. Or you can also try Rocky Mountain Montesa. No idea of their web adress

One more thing that no one has mentioned. Make sure that the flywheel key has not sheared. They were prone to do that and makes the timing to go out of whack and virtually impossible to start.

And the best of luck trying to get that primary gear off if you are going to restore the bike. I have found they come off really easy sometimes or can be a pain in the you know what to get off.

I tend to agree with Arrdy. Not many people out there are cashed up to go and buy the latest trials machines and in some cases you have to improvise. I remember the first bike I built from bits and pieces. An old Bultaco frame, Montesa motor, Honda seat and all the other bits from God knows where. It was not pretty to look at but it beat the pants of many other other modern bikes. Wish I had it now but sold it for next to nothing about 35 years ago. Currently working on a Cota frame with a honda 250 4 stroke. See what happens. May come to nothing but hey it's fun and that is what is all about isn't it? Why fork out good money when you can build something yourself.

Thanks David, I think that is your name as you have helped me out a few times before. I will plug away on this and get back to you when I work out a way to put a motor in there somehow. See ya mate

Hello people. I am after some ideas here for an engine conversion for a Cota 348. I bought the old Cota as a donor bike for the other 348 I have and after a few years I have pilfered so many parts from it (mainly motor parts) that it would be virtually impossible to put the Monty motor back in. Apart from the motor, the rest of the bike is still intact and it seems a shame to have under the house doing nothing. I was thinking of a 4 stroke, 250cc size. Has anyone seen or heard of such a conversion? Any help or leads much appreciated. Thanks

Didn't know that. Only trying to help