lemur

First off we have no idea what part of the world you live in so your availability to procure old gasgas parts is difficult to predict. Your front disc brake has 2 pistons, after Y2K 4 piston brakes became the industry standard and 4 pots offer noticeably better performance. Top end is part of it but from what I've seen with gasgas over the years, the main bearing seals are another item that may well require replacement. As previously; how easy does the bike cold or hot start? <- That is possibly the most important indicator of the bikes current health and worth.

I bet it's a JTX270 from 1997 but you could tell a lot more if you could see the rest of it, front brake is candidate for upgrade, does it start easy and run good 👍 that's the main thing. Compression test is always a good way to start evaluating an engines condition if that is an option.

Probably not. Jitsie is a unique and new company, they specialize in online trials bicycle and trials motorcycle parts and accessories because prior to their start up nothing like Jitsie existed. Store front operations don't normally promote online inventories because they have their money invested in a store front. Most trials bike dealers that operate in rural areas work out of a van, trailer or truck so they can have their inventory mobile and available at events. If you are at an event and break something a dealer might even have what you need when you need it, if the business model is online shopping you would be waiting for parts to be delivered after the event and subject to additional shipping costs.

... remove the rear shocks and move the swing-arm through its entire travel, if the rear brake actuator lever moves (brake applies) when the suspension moves through its travel then the brake needs rework. Would not be a problem if the rear brake was cable actuated.

Looks ridable to me except for maybe the brakes, I think if the engine runs decent I would just sort out the brakes and ride it 😎

Basically, your 75W90 gear oil will be a little thicker at cold temperatures then recommended by the manufacturer. Personally I would be using ISO 46 UDT hydraulic oil because then my clutch won't drag even at cooler operating temps.

Different types of lubricants use different scales: ... when you see 2 numbers divided by the W that indicates an SAE multi-grade blended oil, like you would need if you were accommodating a wide operating temperature range.

It's a little simpler then that; All 2-stroke engines need main bearing seals to function. Crankcase on a 2-stroke engine is used to force air and gas mixture through the engine via vacuum or positive pressure differentials, if the 2-stroke crankcase was not sealed on at least one side of a main bearing the engine would not function because air pressure differentials caused by the movement of the piston would leak past the crankshaft bearing. A crankshaft roller main bearing will be open to whatever side it receives lubrication from, be that via lubrication in an adjacent transmission case or via oil pre-mixed in the air/fuel mixture.

Curious, does the front brake calliper fit the rear brake mount? That would greatly simplify replacement.

The riders that you would be competing with are the ones you will learn the skills from and competition motivates you to learn and apply those skills. Best thing I ever did was start amateur trials competition and the skills didn't significantly develop until after that happened. It's too easy to never challenge yourself or to find reasons not to ride, riding with others that have the same interest is the best motivation. Riding with better riders makes you ride better.

Many sell Jitsie

Throttle down, shift up, work the clutch and get good at one finger braking 👍 then you can safely start to follow better riders and learn technique. Find the gear that takes you from zero to all you will ever need (usually 3rd on a 300cc) leave it that gear until you can ride that gear with good control on any terrain. As a senior citizen I prefer the larger displacement bikes because I don't need to ring the snot out of a little tiny engine to make it work.

Jitsie

The 2 high tension wires that go to the starter motor? Those wires would need to remain that thick or the batteries and relays need to be moved very, very close to the starter motor.

Oh heck no! and if I did break something at yesterdays trial, I would have had it fixed ready for todays trial 😎 D&J stock the parts you are likely to need.

Gotta get my parts from somewhere.

Yep constant, you must not be riding anywhere near the hours I do now, I'm retired and all I do now is ride motorcycles. Currently a 2017 Montesa and a 2020 TRS and planning to trade my TRS in for a new one this year or next spring.

All of them are constant maintenance, what brand would provide you the best dealer/service representation? <- that's the one to roll with. ... my TRS dealer is only 20 feet away at the moment and he has a truckload of spare parts 😎

Sorry I didn't realize FAA documents are 'random lethal articles'. " transition to lead-free aviation fuels for piston-engine aircraft by the end of 2030" <- that's 7 years and hopefully well within my lifetime.

Poisonous and lethal are the correct terms now that we know better and we know better because we (humans) abused the use of TEL to the point where it has become a global problem for all life. https://www.faa.gov/about/initiatives/avgas#:~:text=The most common and reliable,damage at higher power settings. LL Avgas is on the chopping block.

You mean all those airplanes that come fitted with 2 spark plugs per cylinder ! Decades ago lead fouled plugs and left visible deposits on every engine I ever ran leaded fuel in. In the 1960's and 70's we went through spark plugs like they were candy. I 'd much rather explain to you the impact of TEL on human and other living things and why you should not be burning TEL in your weed eater today. ... I'm a field naturalist but I guess you can call me a tree hugger so from where I stand you are not just breaking federal law you are breaking the law of nature 🤔 for fun

For wet clutch and transmissions I use the same thing I use in my Kubota tractor or excavator transmission & hydraulics. Works out to around 8$ per litre or less then half the cost of motorcycle lubricants so I can change it more frequently and that's the ticket to better clutch performance, you need to keep the dirt and water out. To the question of mineral oil, yes it's been around almost forever, Norton brand honing or sharpening stone oil is a very thin, food safe, pure mineral oil and works great in a clutch hydraulic master cylinders as well as for lubricating cables and mechanical parts where a thin oil is called for. Been using both types of oil successfully in all brands and types of motorcycles for decades.

Not cool to run leaded fuel in a Montesa and that could definitely foul plugs through lead deposits. and it's illegal.

Neoprene boot gaiter

Indeed, his is even more simple, it has fewer parts by one and one less component connection to be concerned about. The fan and its power requirements are virtually the same.