aussiechris

I'm pretty sure the alternator output is 160w. Without lights there should be plenty to spare. ECU and fuel pump should only need about 20w. Not sure about the fan but probably another 30w or so. If you're running the homologated headlight then that could be 35w plus tail light etc.

Seems like there are problems with both types of forks. Unlike the Tech forks, the problem with the Showa forks is not really the seals. It is the teflon coating coming away from the top fork bushes and bits of it getting caught under the seal causing it to leak. Eventually you will have metal to metal contact with the fork tube which won't be good. This is what a faulty bush looks like (and that's not wear and tear):

Unfortunately, the dealer(s) here in Australia claim not to have heard of any problem. They've obviously not heard of the internet either. To each individual they will tell you that you are the only one to have had this problem (implying that it is your fault somehow). Clearly, there is a real problem with the Showa fork bushes from 2015 onwards. I say onwards because, as Oz Thumper says, the replacement bushes are failing as well. Very disappointing.

Wow, if the H and D plate is softer than the OEM one then I'm in trouble. The original plate is thin and soft like cheese. I press mine back out using a hydraulic press every couple of weeks. It fits back on fine after doing that but I'm desperately looking for a replacement. I will check out the Mitani one. Thanks. Chris.

Thanks for all the replies. I'm not terribly concerned about warranty. Over here most folks assume we have 3 months on a dirt bike, but there are statutory warranties as well. Something like this kick start lever would be difficult because the dealer could just claim it was operator error. In any event, I will contact the dealer and send him the photos and see what comes of it. But I expect I will be doing the fix described by Jimmyl above. I could also grind it out and build up the lug by TIG welding but that will be even softer than the original. Chris.

I was wondering if this is common or just a one off. My less than year old, 2015 4RT has a problem with the kick start lever. The lug that engages when it's folded out has cracked and deformed. It seems the alloy is really soft. Apart from putting the lever at too much angle, I can see this is going to fail in the middle of a ride somewhere. This bike hasn't had that much use because it's not my only bike. And other bikes I've owned have never had such a problem even after 10 years of hard use. And before you suggest it, I am very gentle on the kick starter. The bike starts better with a slow push than a stab. I'm happy to purchase a new genuine lever but not if they are all this bad. Has anyone come across a decent aftermarket lever? Chris.

I had one fork seal start leaking quite early on (this is Repsol with Showa forks). I too was surprised that this would happen. Upon dismantling the fork, I discovered that the top bushing was faulty. The grey teflon coating was flaking off and bits of it getting into the seal area. I replaced the bush and the seal with genuine parts (both low priced). I like the genuine seal as it is a full double lip (two garter springs) seal. Those green SKF seals look good but are too expensive (at least 4 times the price of a genuine seal). You can get the genuine one from any Honda shop because it fits one of the old XR models. Just quote the part number 51425-NN3-821. It was about AUD$17 from either Honda or the Montesa dealer. The bush was about AUD$12 from the Montesa dealer. Again, this refers to the 39mm Showa forks only.

Normally you would pick the map you like then check if the switch is shorted or open circuit using a multimeter. Then simply disconnect and remove the switch. If your preferred position is with the switch in the open circuit condition then just leave the wires on the wiring loom disconnected. If your preference is with the switch closed (shorted) then you will need to connect the two wires in the wiring loom together. Chris.

Agreed. Use the HK1520-2rs bearings and then you don't need the OEM type seals (which leak and fall out). The dog bones are 20mm wide. You will probably still need to source the inner rings (bushes) as a Gas Gas part as most bearing suppliers don't sell them. Gas Gas part numbers are BT27712014 (20x15x8mm) 2 required and BT27712005 (20x15x10) 2 required. This only applies to the four dog bone bearings. There's another two in the underside of the swing arm with two 3mm wide seals. You can't use the HK1520-2RS in there as the total width will be too wide (40mm vs 38mm total). But those bearings a well protected and don't give as much trouble. Chris.

Yeah, check the front fuel tank bolt and also the exhaust mounting bolts. And, of course, engine mounting bolts.

Yes, you install that bush after assembly (before installing the sprocket). Sometimes it's a bit of a squeeze to getting it in all the way and you need to push the sprocket up against the bushing while installing the circlip. And it certainly looks like those cases have a busted lower engine mount. They should really be replaced or repaired. Been there, done that (a quick search will find my thread on why that happens). Chris.

I think the couple of turns you undid it was just the spring pre-load adjustment. Now you've reached the end of that, you have to lean on it a bit more (while holding the lock nut) and it should come undone. When you do it up again, the same will apply. The first so many turns will be the adjustment, then you need to nip it up. No need to over-tighten. Chris.

Thanks guys. That's all good information. I agree that some insulation will be the answer but I don't want anything stuck to the bottom of the pump that will hold moisture and cause rust. But I am very interested how that material goes ChrisA. Certainly, keeping the fuel topped up will help. The question of what fuel to run is an interesting one. I've been running 95 for no particular reason. The bike can be a bit frustrating on warm or hot starts often taking two to four kicks. I just thought it was poor technique as I also ride a Gas Gas. The gasser needs throttle and a sharp kick while the Monty is the opposite. But the Montesa starts 1st kick from cold every time. I checked the valve clearances today and they were spot on. Same for plug gap. So I will try running 91 octane fuel next time. Again, thanks. Chris.

My TXT321 had copper washers under the head bolts but that was a 2001 model so may have changed. The stuck fork adjuster will most likely be that the spring and ball detent has rusted up (that's the bit that gives the adjuster nice little clicks). There is a small allen headed grub screw (part 29 in your diagram) that screws into the side of the cap. Under it is a spring (28) and a ball bearing (27). On my bike that spring was rusty and the ball was stuck. I suggest you try to remove the grub screw and spray some penetrating oil in the hole. Then try moving the adjuster and/or removing the spring with a pick. Be patient and don't round out the hex in the grub screw - it's only small and can be tight. Yes it is a cartridge fork but the damping adjustment valve is all contained in the cap unlike the later models. Edit: And yes, you need to loosen the top fork clamp pinch bolt before removing the cap. You don't really need to remove the whole cartridge - just push the lower part of the fork leg up (wheel removed) after undoing the cap and the cap will come up with the spring and everything. Then you need to push down the plastic spacer, compressing the spring and get a spanner on the lock nut under the cap. Then undo the cap off the damper rod. It's a three handed job! Chris.

Just wondered if others had encountered this issue. I rode a fairly tough two day trial this weekend and every time I re-fueled I noticed a lot of pressure built up in the tank when I removed the cap. A look inside revealed the half tank or so of remaining fuel was actually boiling. It was warm weather around 28°C (82F) but it will get a lot hotter than that in summer. I've only owned the bike during the winter months so this is the first time I've seen it. It appeared to have no impact on engine performance - it ran fine all weekend. The engine is not overheating but there's clearly plenty of heat getting into the tank especially when parked even with the engine off. At least I know the one way valve in the vent pipe is working! I am curious as to any potential damage this might be causing (and I'd hate for it to blow up while I'm riding). Chris.

According to the 2011 parts book for the standard (non-raga) models the part numbers for the 125 is different to the bigger bikes. Left crankcase MT280310001RA for the 125 vs MT110002811 for the 250,280,300. Right crankcase MT280310000RA for the 125 vs MT100002811for the bigger bikes. However, the later parts books suggest they are the same. I didn't see where you hail from but Paul (above) is our Aussie dealer and he would be able to help with part numbers. I don't envy you trying to get parts right now so you might have to shop around. And yes, if possible get the 2012 or later cases because you can replace the gear shift shaft without splitting the cases. Chris (been down this road before )

Glad you got it sorted. Yes, it's bizarre that they stick with the loose roller bearings. But in theory, the full compliment bearing should last longer than the caged version. I remember owning a Montesa 172 Cota which had loose needle rollers in the small end of the con-rod. Pulling the piston on those bikes was common due to carbon build up. You soon learn to have rag stuffed in the crankcase when trying to re-install the piston pin through those loose rollers. You also learn a lot of patience. BTW, Nice countryside where you are. Chris.

I would dearly like to find a set of triple clamps that would give more steering lock. Coming from a Gas Gas or Beta, I find this is the biggest problem with the Montesa. It just doesn't turn tight. Yes, I know I should learn to hop and do tricks more but I'm too old for that, and it's not much good in a no-stop trial. Chris.

The above replies are spot on for replacing the bearings. As for options, I haven't heard of anyone using bushes instead of bearings but there a a couple of options for you to consider. This is from a post I submitted ages ago but is still current... Virtually all of the kits sold by dealers include bearings with separate seals. In my opinion these are rubbish. And yes, I know that's what comes from the factory. The original bearings are HN1516 which is a full compliment needle roller with a 15mm ID, 21mm OD, and it's 16mm wide. The supplied seals are the same dimensions but 2mm wide. That makes for an overall width of 2+16+2= 20mm. There are a number of reasons why they fail early. Firstly, the needle rollers have little tits on each end to locate them in the housing as there is no cage. For some reason, in our application, those little tits break off and get in amongst the bearings causing failure. But the main reason is water ingress. Those 2mm seals have a steel shell and that doesn't seal too well in the dog bone as it is so thin. Furthermore, sometimes the seals just plain fall out of the dog bone. The reason is quite simple. The overall width of the bearing and seals is 20mm, but if you measure the dog bones you'll find they are only about 18.8mm wide. This means (assuming the bearing is perfectly centered) that the 2mm seals have just 1.4mm to seat in. And since the seals have a bit of a radius on the inside, there's bugger all holding them in place. The bearing you want is a HK1520-2RS (contact a local bearing supplier with that number). That bearing is a caged roller with in-built nitrile seals. It is 20mm wide but even though it is slightly wider than the dog bone, it is all one piece. I've been running these bearings for about 10 years now in various bikes. You can expect 5 to 10 years life out of them compared to less than a year from the standard ones. Price is about the same. Even though the original bearings have more rollers that doesn't help if they're full of rust and mud. This only applies to the four dog bone bearings. There's another two in the underside of the swing arm with two 3mm wide seals. You can't use the HK1520-2RS in there as the total width will be too wide (40mm vs 38mm total). But those bearings a well protected and don't give as much trouble. Also, you may have to get the inner rings (bushes, sleeves) off your dealer as the bearing shops seem reluctant to hold them. Gas Gas part numbers are BT27712014 (20x15x8mm) 2 required and BT27712005 (20x15x10) 2 required. Hope that helps, Chris. ps. the 5 to 10 year life suggested above is for Australia where it is very dry and includes regular re-greasing.

That is strange that it showed as no spark. Perhaps the ECU decided the Throttle Position Sensor was out of range. Even so, it is supposed to still run just with poor throttle response. Handy to have one more check (idle speed adjustment) in the fault finding arsenal along with the rectifier possibility from honda_freak. Glad you got it running again.

According to my 2015 owners manual, if the engine does not start you should check the “engine does not start” items below (using the special PGM-FI checker box)... Cause - Symptom Faulty ECU - Engine does not start Open or short or faulty Manifold Absolute Pressure sensor – Poor idle Open or short or faulty Engine Coolant Temperature sensor – Hard starting when cold, fan does not stop Open or short or faulty Throttle Position Sensor – Poor engine response Open or short Inlet Air Temperature sensor – Engine operates normally Open or short or faulty fuel injector – Engine does not start (would still have spark) Open or short or faulty bank angle sensor – Engine starts but stops after a few seconds. It goes on to say that if the above checks out ok, then replace the condenser with a new one. If the engine now starts then the old condenser was faulty. Just for testing purposes, you could go to an electronics store and buy a 10,000 microfarad capacitor (at least 35 volt rating) and connect that in place of the original one. Ensure you connect the negative terminal to the earth side (green wire) and the positive to the power side (red wire). I don’t believe having the alternator disconnected will cause the ECU to lose memory (the maps and program are all in Flash memory). Since you say the plug is getting wet with fuel, this would suggest the ECU and fuel injector is working. Looking at the other “no start/no spark” items, I think you’re left with the ignition coil (and associated wiring) or the condenser. You’ve tested the coil on another bike so it’s either the coil wiring (did you try the other guys coil on your bike?) or the condenser. I hope you find it soon. Chris.

Yes, the selection of base gaskets is so you can set the piston to cylinder head clearance (squish). You can use one or more gaskets to get it right. If you do a search on setting squish clearance you'll get all the info you need. Basically assemble the cylinder with one gasket (no need for piston rings at this time) and bolt it down. Shape a piece of soft solder (about 1.5 to 2mm diameter) so it sits across the top of the piston with the piston just below top dead centre. Install the head (no need for o-rings at this time) and tighten the head bolts. Then crank the engine past top dead centre. Remove the head and the solder and measure the thickness at the ends of the solder where it is squashed flat. Not sure what it should be on the older bikes but I run about 0.9 to 1.0mm on my Pro. Simply calculate and adjust the thickness of base gasket(s) until you get it close. As for pistons and rings, the old ones where made by Mahle (and were excellent) but they stopped doing bike pistons. S3 are now doing them but the rings are not interchangeable. So shop around to see if any shops have old stock of the original rings. Chris.

Yes, I would torque the fork clamp pinch bolts. The spec I have is 8 ft/lbs for the top bolts and 10 ft/lbs for the lower ones. That is for my pro but should be the same if yours has 6mm threaded bolts. And you would also have loosened and re-tightened the fork brace (mudguard bracket). 6 to 7 ft/lbs for those. Chris.

Sounds like you've done a pretty thorough job checking every thing including the eliminating the back angle sensor and ignition coil. Using a test lamp to check voltage going to the coil may not prove anything (you'd have to try your lamp on a working bike). The attached image shows how short those pulses are (that's measuring the coil terminals on my 4RT idling). Assuming no wiring faults I think it's starting to point to a crook ECU/throttle body or faulty condenser. Any chance you could borrow such items to substitute? Chris.

When you say "linked out the kill switch" do you mean you by-passed it with a wire link. That wouldn't be right. The kill switch shorts to ground when you stop the bike so it should normally be open circuit. So to test - just disconnect the kill switch. Make sure the kill wire to the ECU is not shorting somewhere on the frame. Otherwise I'd be checking the coil next. Chris.