Online manuals are easy but thank-you. Document the heck out of that part if you are going for a new engine, hopefully that happens. I'd be most worried about heat near the exhaust valves and would be inclined to take pictures of inside the top end.
Check that your oil delivery hole is not plugged, possibly even since new, somebody just now reported that issue on a 4-ride, & that would certainly account for an engine knock.
... The main bearings are shells so will suffer badly from a lack of any oil supply.
Not sure why the engine has not protested yet? Any ideas?
You got a part number for that shell bearing? 🤔
I think the oil pressure is mostly top end and you haven't experienced problems yet because it's built really well and the oil in the wet sump and splash off the cam chain was sufficient to stop it from imploding.
Snow was too deep to ride for a couple of weeks but conditions are improving 👍 at least I can ride the lake and the snowmobile tracks now, just wish I had made way more tracks. If you're planning on riding winter trails where there is snow accumulation figure on needing a trail groomer or two.
Hey Emlyn, I had one of those once, had to rewind the alternator coils when it burned out. The 12 volt rectifier you need is nothing special you can use one from almost any similar motorcycle, same with your rear brake master cylinder, should not be difficult to source either of those items.
Worst feature of the bike is the air intake doesn't like deep water crossings, that's what eventually killed mine, try not to drown it.
Made a set of custom brake shoes for a friend that rode one of those, I used Thorndon XL elastomeric bearing plastic and it made the front brake powerful enough to do nose wheelies, unless you run them hot enough to melt the plastic, that was not so good 😆 Not saying I would recommend that exact modification unless you regularly ride in deep water, but it's worth mentioning that there is another way to approach the problem 🤔
Using mineral oil for any hydraulic application that won't end up oiling your brake pads is a brilliant move. To minimize the number of fluids that you use for maintenance buy Honing or Sharpening Stone Oil which is food safe mineral oil and excellent for lubricating anything that needs a light oil. Norton brand is what I've used for decades in all kinds of applications and it costs ~20$ per quart which will last you almost a life time if you only use it on your motorcycles.
about to buy a trials bike and riding gear! Absolutely new to this been road riding and trackdays for years but wanted another hobby for new skills!
Advice on second hand bike and kit please..
👍🏼
Buy something built in this century and fitted with 4 piston front brake, 2 piston rear brake and most important it needs to start easy. For gear you will want an open face helmet, gloves, proper trials riding boots and a back protector is recommended or required once you plan to ride in competitions. To advance your riding skills fast you will want riding partners, ideally someone riding at a higher level than yourself that you can follow, plus a venue that features some challenging natural terrain. Trials bikes are among the most expensive motorcycle per pound you will ever buy but cost of operation is relatively low, they don't break easy and they burn relatively little fuel, however replacement parts like fenders and tires will be expensive. If buying used, plan on spend almost as much time servicing your motorcycle as riding it.
Too new to expect serious problems, I would check the plug gap or replace the plug, check the air filter for cleanliness and the correct saturation of filter oil, basically anything that would cause fuel to incompletely ignite in the combustion chamber such as the ignition timing.
On the up side the 4RT engine is designed to survive low oil pressure far better than a regular Honda engine costing near half as much, there are roller bearings instead of oil pressure bearings or on near everything.
If the Oil Strainer Screen is plugged the pump and filter will starve. I didn't see mention of the strainer screen outside of the Engine Oil Flow Chart pictured above.
Need a better description but if it shifts through every gear and the lever springs back to centre after shifting, you likely have it together right, how well everything slides is dependent on how careful you were on assembling all the sliding parts and condition of the shifter forks, bent or worn shift forks will cause imperfect movement of the spur gears but you should notice that on disassembly or by the metal shavings in the oil changes. What was the condition of the shifter forks when it was apart?
You can get more from just looking at the parts diagrams. Twin map on a carburetor bike is just an ignition retard or advance, not much more it can be.
Pro for the Honda engine is the relative engine parts availability. Fantic is potentially more competitive if you can keep it running. Much depends on terrain and level you plan to ride to. Fantic is a hard sell where I live, ymmv.
I have a Montesa Engine ( i am pretty sure that it is a 360 Enduro motor. Can anyone identify the year and model? the number on the engine is 67M0201 I am looking for a rolling chassis to go along with this engine. Thanks!
I think you are looking at a 1978 or 1979 360 Enduro 👍 sweet bike, I bought a 66M in 1976 but that is the 360VA Motocross version 👍 awesome bike, wish you had an engine for that one, I'd buy one of those in a heartbeat.
Bought this trials bike for my 6 year old. After some time we ve finally got it working but the fan that came on the bike looks like it's been a make shift fan and is completely knackered and fell to pieces.. can anyone help me with this, such as will any size bike fan fit, does it have to be from another txt boy 50 bike?? Or does anyone have one that can be purchased??
GasGas parts manual on bike-parts-gasgas lists the fan for the 2005 TX50 as part BT720003013. and that is the same part number as a KTM and Husqvarna fan, but they say contact them to order because I suspect they are going to tell you the entire stator and magnet need to be replaced as well.
The fan runs off DC so there is a small rectifier on there to convert the AC coming off the existing alternator, if I was you I would start by testing the voltage output from your rectifier and then you can source a small muffin fan to suit the voltage and mounting space. Muffin fan is what they were originally called and they are available in a vast range of sizes, muffin fan power requirements start at 5VDC which is USB standard and if your alternator can't power the fan you could add a rechargeable battery to run the fan dead loss and recharge it when you're not riding.
I do know the stuff. Are you saying this because you’ve also had this issue?
Yes to that, all the way back to 1970' twin shock bikes I had throttle cable kink issues that became a problem, but I never had to replace a throttle cable on any of my 4RT rides because I wrapped the cable as soon as I bought one. I do the same thing with my TRS bikes now, although the TRS throttle cable has less tendency to kink the shield at the connections and only needs covering on one end of the cable slack adjuster.
I always wrapped that part with the spiral plastic that you use to bundle electric wires together, put it on before the cable is too badly kinked and it works great. Search 'spiral wire wrap'
Montesa 4 Ride Oil Filtration Issues
in Montesa
Posted
Online manuals are easy but thank-you. Document the heck out of that part if you are going for a new engine, hopefully that happens. I'd be most worried about heat near the exhaust valves and would be inclined to take pictures of inside the top end.