lemur

You are building brake parts 🤔 are you trying to build up a dimension on the brake pad steel backing plate? why not use JB weld epoxy or something similar to build up the surfaces and then file it to precise shape and fit?

Holy 50 hours is far off the 6 or 7 year failure interval that I have been seeing, even on Honda generators. We are only talking about adjusting out the amount of metal fatigue and deformation in the valve seat here. The Montesa engine has a decompressor on the cam that is dependent on the clearance adjustment being spot on, I just checked a Beta 4T manual and the Beta 4T has a similar decompressor mechanism on the camshaft.

All of my Honda engines had about 6 or 7 years of heavy use on them before the valves needed slack adjusting. It would be no surprise if a 9 year old Beta 4T is due for valve clearance attention, ymmv. A compression test 'might' be an indicator of valve clearance problems, but only if you have compression test results from when the engine was new to compare with. Carburetors and modern pump fuel with the corn alcohol added is a problem because carburetors have a vented float bowl where fuel can evaporate and leave behind residue or promote the growth of organic materials, by contrast fuel injection is a closed loop pressurized system other then the fuel tank itself so 'if' you never needed to clean and service a carburetor after running and storing modern pump gas in the carburetor, that would be absolutely amazing.

Brake master cylinder reservoir has a rubber baffle in it to keep the fluid separate from the vented air space above the fluid. It would be virtually impossible to over-fill and pressurize the reservoir unless you left the rubber baffle out completely, plugged the tiny reservoir vent hole and over-filled the reservoir. The rubber baffle is in the master cylinder reservoir between the fluid and the vented area in order to reduce oxidation and absorption of water from the atmosphere by the DOT brake fluid. The little stainless leaf spring part is called the anti-rattle clip.

I rode Montesa 4RT for years and find them easy to work on if you can just replace parts you smash on rocks and occasionally adjust valve clearances good. Friends that own the Beta 4-stroke have a lot more problem with starting the engine cold or after a tumble, the Beta carburetor is a down side when compared to the Montesa PGM-Fi You set the valve clearances when the bike becomes hard to start and you have ruled out everything else. Beta 4T handles nicely, slightly more lively then the Montesa chassis, but the engine performance really would improve with the addition of fuel injection.

Two things I would check, make sure both pads are moving and one side isn't stuck. Second is replace the wheel bearings, the brakes can't work great if the wheel bearings are not great.

Check out Outback Trading Oilskin overpants, might work for you

Ever try to ride over one of those cows? I tried once but he kept moooooving🐄

It's 6 volt is it not? adding a capacitor in this case 6 volt that will smooth the voltage spikes, you could add a rectifier if you want to make smooth DC and if the voltage is not right you add voltage regulation on the nice smooth DC output then you can even set it up for LED or low voltage incandescent. In the olden days it was done with a Zener diode which was a cheap and easy way to both regulate and rectify voltage, might be one of those on there now or should be, wiring diagram would tell. ... yes awesome price the OEM headlight if perfect is too valuable to leave on for serious riding.

I doubt it is a problem for the OP as this was posted in the UK forum section however; DOT in USA is federal law. Federal laws may be enforced differently between the states but the intent of a federal law is to apply nation wide. DOT approvals are only a concern if the vehicle is to be plated for public roads and highway use in North America, same as it applies to quads which also run tires not suited to road use, quads and dirt bikes require an ORV license plate, insurance coverage, appropriate safety gear plus a driver license to enjoy limited secondary road use of ORV's in North America.

I think full size wheels that fit the modern competition tires is very important even for a beginner, tires make that much difference.

Today was Unicorn day 👍 best conditions so far this year 10 out of 10 with studs on a trials bike, this spot looks flat on camera but it's steep, studs are required.

Several of my friends have done the SSDT but they are younger highly skilled riders with deeper pockets 😎 my bones ache just thinking about it.

Still easy, bearings that are used in the wheels and suspension are nothing special, measuring the dimensions in mm of the destroyed bearings and the part that rides in them is sufficient to arrive at a bearing number, or you can reference the bearing size from a service manual, or search for a web site that has decent trials bike parts listings. Buying twice as many bearings as you need right now is never a bad idea, that way you won't have problem identifying or sourcing them next time. I buy 6004 wheel bearings 6 or 8 at a time because they don't last very long and that is the more expensive units. Price and quality of the wheel bearings varies greatly, same as fork seals you can buy cheap ones that are near garbage for the application or buy expensive ones that are just barely good enough. Cheap roller bearings typically have fewer balls and or less accurate clearance tolerance. Trials bike is an exercise machine compared to riding a street bike, you are going to rediscover muscles that you haven't used in decades and investing in a good trials helmet, trials boots and back protector will improve your riding experience greatly.

Bearings are something you can walk into a local bearing specialty store and buy locally and alternatively there is a company called Jitsie you need to familiarize yourself with. 32 years with no trials bikes must have been terrible!

So cool when the snow crust supports your motorcycle and you can ride everything that is white and everything that is not 👍

Somewhere nearby that sells scrap Yamaha ATV parts.

Is that Maxima extra4 full synthetic 4-stroke multi-grade engine oil that is available in SAE0W10, SAE10W40, SAE10W60, SAE15W50 and SAE5W40 🤔 ?

That would be rear wheel travel and not the shock length, 150mm = roughly 6 inches, the shock absorber overall length is close to 16"

I believe the stock shock was made by Betor and ~400mm most I've seen are fitted with a dual rate spring that is almost coil bound through part of it which looks strange. Never seen one with a complete modern front end attached but I imagine that would result in a serious upgrade. Your stock steering head bearings are only loose ball in cup type, a taper bearing set in the headstock would be advised because that is an inexpensive upgrade that gives noticeable results.

All good advice above, a place to ride, people to ride with and a pocket full of money for initial buy in will net you an exercise machine that is So much fun to ride it is addictive. A modern trials bike can do amazing things with easy once you learn enough and develop some skills. Trials bikes are relatively hard to damage but they do require a lot of regular maintenance, you will need a modest tire, parts you do manage to break or wear out, fuel and riding gear budget because everything is expensive ... and if you get any good on the Trials bike it will make you a better rider on every other kind of motorcycle, that will happen some time after you become addicted, develop muscles in strange places and start looking at everything like it is something you could imagine riding your motorcycle over. It's not really a Hobby, Trials bike riding becomes more of an addictive fun exercise life style regime where you meet loads of interesting new people and have fun crashing a lot 😐 which is also part of it, you will crash on occasion and that is not for everyone.

TLR200 parts diagram for the front forks shows no replaceable slide bushings, so the stock front forks are not particularly rebuildable, once the lower legs are worn oval on the inside the forks are done. Springs you can get if the springs in it now are bagged out. ... and you can get seals on spec.

Falcon would be a good start because they list specs and with specs you can search for other options.

Do you still have the original manual? Almost certain it came with one like the 360VA did.

" Marking a National for the NATC is crazy amount of work in comparison. Hundreds of stakes are needed. " Perfect example of why the venue should have some latitude over the marking schema, I don't use hundreds of wood stakes because I have millions of trees. Paper markers 👎 adds a printing cost, paper curls up and markers become unusable before the event even starts, totally useless in the rain, never reusable and impossible to recover without leaving staples stuck in the live trees. Perimeter tape is rarely used to pinch in a section here, we don't need to do that, perimeter tape is kept well back where riders are unlikely to tangle with it, why; because I have yet to see a rider dismount to fix a perimeter tape or replace a section marker after they displaced it.