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Well I am finally done round 1. The Montesa is back together and running. I tore it down to the frame, painted and rebuilt it. New rear shocks, tires, seat and 1 new lower fork. It took me 1.5 weeks to get the forks off and now I can rebuild the front end in 30 minutes. Fun and a lot of learning. I still need HELP! Front forks are rebuilt but I have parts missing. 1 fork was seized - it was missing the lower fork piston bushing. I had to get one machined and then honed down to fit. It works amazing now BUT this fork is 1.5" shorter than the other. The shock I did not rebuild it missing something in the top half of the fork that stops the piston. Explanation - Front Fork - Top Nut - main spring, piston - So top half of fork when I look down I see a square stopper that stops the fork piston. On the shock i rebuilt when you look in you see a stopper or spacer in the tube. I did not want to try to push this part all the way up the fork tube in case it got stuck. So I assume I rode it this way in the 90s. BUT the forks are not balanced, so when you rebound only one fork would top out and the springs are not equal pressure. Will it damage the fork over time? I found the manual but the parts are not listed anywhere. Thanks Francis

That is absolutely gorgeous and it sounds amazing. Well done!

I can order ELF HTX 740 as a Honda original part or special order it from somewhere that won't ship it here anyway and would cost me about 70$ per litre 🤔 do you think SJ grade oil is worth 70$ per litre? You don't pay that for oil bottled in France on your side of the ocean but you still pay exorbitant prices for simple oil that only needs to last several hours before being replaced. Sorry but I pay 10$ per litre for oil that works just fine because it gets changed frequently which is why I don't have clutch problems.

I run 3 psi in the rear. No problems yet but I'm not a top level rider - nothing too agressive.

Sorry to do this but ELF HTX 740 is very well known in the trials community as a for use in wet clutch trials motors , regardless of what it states on the labels .More specifically for use in Honda trials clutches and has also been used by some riders in other brands of trials bikes for many many years.

I've done exactly the same, what a difference .

OK GUYS, JUST TAKEN THE ORIGINAL DUNLOP REAR TYRE OFF MY 2023 MONTESA 4RT. ( yes not had a lot of use as i also do pre 65 and have had an injury ) IVE REPLACED IT WITH A NEW DUNLOP GEOMAX TL01. IVE HEARD THAT THE SIDE WALLS ARE VERY STIFF AND HAVING JUST DROPPED IT OFF ITS STAND ONTO THE FLOOR IVE GOT TO AGREE. I KNOW THEY'RE STANDARD KIT ON THE NEW BETA RANGE. JUST WONDERING WHAT PRESSURES PEOPLE ARE USING , DOES THE WALL GET SOFTER OR IS THAT THE DESIGN OF THE TYRE. JUST CURIOUS, I RAN THE OTHER DUNLOP ON 4PSI. THANKS EVERYONE.

It's only 6 times the cost of what I've used for 20 years. I recommend frequent fresh oil changes with oil that states it is good for wet clutch applications.

I hear you lemur but that’s what’s recommended in the manual, I’ve used it in mine for 5 years without a problem except for the hole in my pocket...... others may join in soon recommending oils like ATF

One season used TRRS ONE RR 80cc y2024 Located in Latvia Price - 2k eur (lots of upgrades, comes with additional parts etc.) For more info - PM

What Elf oil are you recommending for his wet clutch application? " ELF HTX 740 is a monograde ultra-fluid transmission lubricant specially developed for dry clutch gearboxes coupled to 2-stroke engines." " ELF HTX 740 must not be used in an immersed clutch."

Replace them with the apico dimpled plates & Elf oil works a treat on my 4RT 260 😀

I guess it could also be air in the hydraulic clutch cylinder / hose. Bleeding that first might be all it needs?

Hi I have no experience with a Sincro, but looking at the diagrams on the Beta website it looks to be very similar to the enduro clutch as below. Although it has pressure adjustment via preload on the disc spring, it still has friction / steel plates in a basket like the EVO. https://www.youtube.com/watch?v=369zIhnzzZo However I have owned a few EVO's and the clutch on those was often grabby. Many people modified the EVO clutch plates as video below. This is a pain of a job, but does help. Maybe worth trying as it is presumably the friction plate engagement that is the issue with your bike - unless there is a faulty / out of tolerance part(s) fitted to your bike. Putoline GP10 oil with frequent changes also helps as other oils I tried seemed to induce clutch drag. https://www.youtube.com/watch?v=EZeOQWhkUCk

4RT has separate transmission oil from the engine oil which is great because you can put engine oil in your engine and transmission oil in the transmission and wet clutch👍 change the oil type and replace it frequently to keep water out of the oil because water makes the clutch plates swell. Occasionally remove and resurface the friction plates to inspect, dry out and remove high spots or irregularities in the friction plate material. Dump the old oil into a clear glass container to inspect for water or particulates. Inexpensive ISO 46 hydraulic excavator transmission oil purchased in quantity is what I use and replace frequently, because at half the cost of specialty motorcycle transmission oils it gets done twice as often and imo works way better. You should experience very little clutch drag even in sub zero weather using ISO 46 Another possible suspect is air bubbles or water in the clutch hydraulics.

Can anybody tell how to stop my 4rt 260 clutch dragging

Has anybody found a cure for the Sincro light-switch clutch yet? I've tried several things to fix it: 1. Changing the pre- installed settings 2. Changing the oil 3. Slipping the clutch in high gear to wear it down Despite this, it still snatches in slow turns, so I can't keep a line in a tight corner. Basically, I spent £7,000 on a bike which is not as good as my old one. Absolutely gutted.

Ergal axle 150grs less than steel one.

It sounds to me you have a very firm grasp of what’s going on and how to repair and set the ignition on this bike. you’ve covered the basics well. New condenser is a great start. I’d be suspect that you needed to replace the ignition coil as the original femsa coils rarely if ever require replacement. However it’s a base covered so good on you for replacing. The timing issue as you mentioned…. The stator plate was fully retarded ( this would mean all the way counter clockwise). We see this sometimes with the points that are available on the market today. The rubbing blocks on the points are of inferior material and wear exceedingly quickly. Often times so much so that the points won’t open enough or at all. So look at your points carefully to see that the block has ample material on it. Make sure the points themselves are clean and free of any oil or dust or debris. Use a fine file or sandpaper to clean. And remember to remove any sanding debris. You’ve lapped the flywheel taper. When fitting the flywheel have the points cam lobe aways from the points as it will allow the flywheel to slip more easily into place. The end of the crankshaft should just protrude a little further or flush with the flywheel itself. Once in place set your point gap first. 16 thou is spec. Once set then adjust the timing by turning the stator plate advanced or retarded to get the correct timing. You’ll need a dial gauge in the bore for this step. Try not to make adjustments to the timing with the point gap. Verify too that your plug cap is in good working order. And obviously use a new plug. NGK BP5ES is the correct plug. However non resistor plugs are becoming harder and harder to find so you may have to settle for a BPR5ES. The points systems usually give good blueish yellow spark. This is plenty. If you’ve got spark move on to fuel. A clogged pilot jet or clogged enrichner tube on the bings and Amals can give problems with cold starts. And finally compression. Primary and secondary compression is important. Primary being engine case compression secondary being top end piston compression. These bike are notorious for needing regular crank seal replacement. Step by step keep up the process and I’m sure you’ll suss out the issue Steve

https://motorcyclesports.net/montesa-honda-resumes-production-just-days-after-major-factory-fire/

Initial assessments following the devastating fire that struck the Santa Perpètua de Mogoda facility last Friday reveal a far more serious situation than initially feared. The fire completely destroyed the company's logistics center, wiping out nearly 11,000 stored motorcycles and almost the entire stock of spare parts destined for the sales network. The damage will have significant consequences for the company's operations in the coming year. https://www.facebook.com/thehellteampage/photos/for-anyone-who-hasnt-seen-the-spanish-news-this-week-there-has-been-a-major-fire/1479928174151275/