Montesa

Trying to avoid egg-on-face when I come to reassembly. In the middle of a strip down and rebuild of a spare 348 engine I bought a while back. All stripped down and parts labelled but… I've got a couple of left-over parts which I can't identify - can anyone help, please? As you can see, there's a spacer and a needle roller. Found in the bottom of the gearbox and can't work out where they came from. I'm pretty certain they were inside the 'pocket' of the crankcase half where the gearshift shaft terminates. Both are 15mm outside diameter, spacer is 10mm in length, bearing 14.8mm. The only place they appear to fit is within the clutch side crankcase half where the …

I need a clutch basket for a 1985 Montesa cota 330. I've looked just about everywhere. Any help would be greatly appreciated. Can the center of said basket be repaired if it's been cracked? Could the center be machined at a reasonable cost?

Hello My 301rr has a knocking noise on low revs. Not sure what it could be but a good mechanic told me it sounds like a worn piston. Bike is a 2020 and it has been used most weekends. Bike has no vibrations and runs great, it doesnt smoke. Anybody had to change their piston on the 301? Could their be other issues with the bike? Main bearings, big end? Or is this not something that goes wrong quickly? Kind regards bob

Today I drove the bike for the first time after rebuilding the engine, unfortunately there is a problem shifting the gears. There are a lot of false nuetral between the gears, is there is some way to adjust the shifter mechanism to get a smooth gear shift.... or have i made a mistake when reassembling the motor?

Hello. I bought a brand new 4 Ride in April last. Ran it in for 260 miles before servicing it prior to a weekend trail riding in N Wales. The oil filter was bone dry with a dribble of oil sitting inside the filter housing. Aaaargh! Fortunately I still had my old CRF for the weekend and the 4 Ride went into the dealer a couple of days later. They said that there was no issue that they could find as they replaced the filter, ran the bike and opened it up again to find oil as they would expect to see. Vaguely reassured, I took it to France for three days trail riding and then to Devon in December, nearly 400 miles. Took it apart for an oil service and found…

Hi, It's been a while since I last posted. I am finally getting round to rebuilding my Cota 349 1979/80 (an early one). It's only been stripped and in boxes and drawers for the last 12 years, so I'm moving quickly on this one🤪. Can anyone let me know the correct piston ring gap for the standard bore please? The bore is good, not oval, and has hardly any wear, so I am just putting new rings in. I have the new rings but wanted to check the gap before assembling. If I remember I'll post some photos along the way. I've already rebuilt and re-spoked the wheels, frame powder coated, new shocks and forks rebuilt and fitted. Going to have to do the forks again tho…

I have a 2005 4rt and was wondering if anyone has the bearing # for the head set bearings? or are they the same bearing used on newer 4RT ?

Plan on posting a photo to show what's going on when I have one, but for now wanted to get this post up. Have a 2017 300RR and when I purchased the throttle cable sheath was broken near the top where it meets the housing on the bars, and the angle of it was sharp as though it was bent. I replaced it, but now 1.5 years later this one is doing the same. I have looked at pictures of routing the cables and I'm not entirely sure mine is correct, but I have seen more than one routing where one goes behind the bars and beside the tank, and another picture of the routing in front of the bars. I just want to stop this happening again, so if anybody has heard of this issue or has a…

Hey guys, I'm new to the 4 stroke game. I last rode a 2018 125 beta evo. I havent rode in 5yrs so was just wondering if anyone had any tips on how to get the best out of the montesa. I'm 18yrs old and looking to compete at a decent level like the old days. Are these bikes as responsive and snappy as a 2t in thr right hands?

I have seen a used engine for sale, can anyone help me identify it, the engine number is 51M7529.

Hello, I'm in the middle of restoring my 348 and I'm trying to fit a Wes silencer but it doesn't line up the the centre box, the bike came without a silencer but has an alloy plate fitted on the frame mount? Anyone seen this before?

I would like to install the Termignoni muffler and header pipe on a 2022 Montesa 301RR. Does anyone know the part numbers for these two parts ?

Hi is it possible to replace the small fuel tank of the Montesa Cota 301RR (2022) with the larger tank of the 4Ride ?? are the mount points identical? cheers, Manu

Hello, Newbie warning: I bought a cota 348 a couple of weeks ago and noticed an oil leak from the timing flywheel cover, pulled off the cover and saw that the case has cracked bý the kick start shaft . Questions: Is it wort welding the case and can I disassemble just the right hand side of the motor? I removed the sprocket gaurd but the bolts seem to rotate what is it on the inside of the case that the bolts screw into?

Can folks give some input on the value of a 1973 montesa cota 247 trials bike? Looking at parting with my father's bike which is not currenlty running and we need a ballpark idea of what to list it for. Thank you in advance.

Hi guys, Sadly we has a fire at our house last week and my Montesa 4RT suffered some fire, smoke and water damage. It’s not insured regrettably so I have to see if I can get it up and running again. The heat and fire damage seems to have affected a few plastics like the rear mudguard and also killed the rear tyre too. However at this point I also can’t get it to start at all, so I’ve been trying to work out what’s wrong in a step by step fault finding basis. The first thing we noticed was that the throttle cable was stiff and stuck and not returning to its home position. We have now removed that and will order a new one. The bike i…

So a 17 plate 4Ride with 230 miles only dont ask its one of 4 bikes i use for green laneing and it gets an easy life I have had it from new. So last year did the MOT only time the bike went out bike started no problem did an hour play then put it away ready for use. so i then fall ill and cant ride for the entire year so pull it out this year as I'm back and fight fit the bloody thing wont start did the reset thing loads of times fuel smells ok spark ok and looks to be wet it will fire with a blast of carb cleaner in the plug hole when put back in where do I go from hear. body work off and get at the injector or is there a quick trick as problem looks to be fuel

Hi guys I have a 2015 Repsol 4RT that has been amazing to ride and I regularly change the engine oil/ transmission oil. On the last change there was barely any transmission oil at all! I have done some searching on the forum and this has been mentioned before - with the crank seal apparently the culprit? Has anyone experienced the same and did this change solve the problem? I'm looking to have this changed, and not experienced opening up the engine so would doubt its a job for me - can anyone recommend a good shop local to Birmingham/West Midlands who'd have experience with Montesas? (BVM?) I was quoted by a Montesa dealer in Yorkshire but don't want a lon…

Has anyone changed sprocket size on their 4ride? Currently i have 10/41 (which i think is stock) Bike doesn't relly get used for "trials" riding, more for really technical trail and woods riding. I think i can sacrifice a touch of slow speed, to make the ride between sections a little more pleasant. I was thinking of changing to 11/41, but not really sure how big a real world effect 1 tooth at the front is. Also, i'd like a steel rear sprocket, but evertyhting i see for sale is aimed at 4RT and therefore weight is key and they are all aluminium.

Hi ive a 315 fully rebuilt in every way and now fitting the rear wheel it seems to become very hard to turn once the spindle nut is tightened. snail cams are in equal positions and the rear wheel seems to be in alignment. I’ve had the wheels rebuilt the swing arm powder coated new spindle bearings and a second hand rebuilt calliper new snail cams chain sprocket disc finally botls . any ideas? cheers!