feetupfun

The front end on this TL125 by Dan Gollagher works beautifully

same comments for MT125, CR125, MR175 front ends as for XL125 leading axle front end

I do know that there is usually no place to fit a compression release on modern water cooled two stroke motors because the coolant space encircles the spark plug. I suppose it could be dome with a lot of machining and welding. An old trick you might consider (but feasibility depends on the design of the cylinder casting) is drilling a small hole from the top side of the exhaust port and through the top end of the cylinder wall. If the hole size is chosen well, it will make it easier to kick over but make negligible difference to the way it runs. Another option is the Beta Alp (4 stroke 200cc Suzuki motor) which is electric start, but not really a competition trials bike

by the time it was 3 years old, our 24V OSET 16 had so many parts replaced there was very little left of the original bike

sounds like typical symptoms of blocked or part-blocked pilot jet

Some Montesa forks use an anti-bottoming device which can swell/bell causing the forks to stick, but that is when they are fully compressed, not half-compressed. It is also possible that one or both of the tubes is bent, and that when you reassembled them into the triple clamps, the bend/s might be causing a sticky spot. I would look for bends in the tubes. If they are both bent you may get away with aligning the orientation of the bends to be fore-aft and both the same way, so that the mudguard mount and axle fixing location holding the fork bottoms in the one position does not cause the bends to cause a sticky spot. Better still to have the tubes straightened. Maybe there is a little dent in one of the fork bottoms that combined with a slight tube bend, is causing the jamming. In this case you should be able to get them to move freely by rotating one or both of the tubes in the triple clamps so that the bend moves the "high" point of the tube away from the dent.

Need more info. You have not said if the shift shaft is frozen, or still moves. If the shifter shaft still moves freely through an arc, it is likely to be a spring broken or popped off behind the clutch basket (no need to split the cases). If it doesn't return to mid position itself after being moved, also likely to be a spring issue behind the clutch If the shifter shaft is frozen it might be bent, or maybe something else - more info needed. Is there any evidence of the shift shaft being out of position axially, or having had an impact? Is the circlip still in place where the shift shaft enters the gearbox on the LH end?

totally agree about the benefits of having an advance curve. That's why I put the ignition on my TY175. It is a 205cc engine and I wanted to make it harder to stall, and also retain top end power

I've witnessed the John Cane type (on one of my TY175s) and the Electrix type (on a friend's TY175) and they both work well. The only negative I have seen is that the Electrix one uses a very long HT lead because the HT coil is located down beside the airbox

LH (ABCD) DT175 crankcase halves are quite different to the TY175, most obviously where the flywheel cover attaches. The closest match would be YZ125C and YZ125X (the first six-speed motors of that lineage), but I have not tried to match up the big TY175 magneto cover to one of those, and they are far rarer than TY175 casings anyway. Later model (EFGH) DT175s with the 6 speed motors are also different where the mag cover attaches, and also have a completely different shift shaft arrangement. I suggest you persist in seeking a TY175 case because they do pop up on eBay. A friend bought a pair of casings here in Australia on eBay only a few weeks ago. You may have to buy a bottom end or a pair of casings to get what you want. If the damage is repairable, just get it to a suitable welding specialist. Maybe if you posted a photo showing the damage, you could get an informed opinion about if it is repairable or not.

I agree with copemech. That's the exact reason we got a 200 Beta for my wife to ride

that switch is not a standard fitment so may be connected to anything, or nothing. Most likely it is an ignition switch so one of the positions is probably "on", and the other positions stop the motor. As far as I know, the standard ignition for those bikes is just magneto, points, coil type. If so, the ignition switch should earth the primary circuit to stop the motor. Most people use a push button switch or a quick release lanyard switch on the handlebars to stop the motor.

google what?

Hard to know if anyone has seen something if you don't show what it is

Winner in each class to score between zero and twenty points per day. A suitable spread of scores within a class would see the median score being between 20 and 60 per day. If anyone gets more than 100 points per day in a class when the winner gets less than 20 in that class, the rider with more than 100 is probably riding in the wrong class. As rabie says, if you are doing stats on scores, make sure that they are actual riding scores not deliberate "fear" fives due to extreme severity, or I-ran-out-of-time fives I always set lines in sections thinking of the capabilities of the least skilled rider I expect will be riding that class The number of sections ridden per day depends on the temperature, rainfall and the length of the loop. Perfect riding conditions and a short loop and not much queueing - 35 sections per day. Very hot - less laps. Rain expected - less laps. Long loop - less laps. Lots of riders per section - less laps.

different name alright but it is pretty easy to work out who it is bodwheel is pretty cool though, sounds like someone who is closely attached to their bike

This Fantic should be a lot better to ride for a learner than the Beta Zero however I want you to know that a more modern bike would be that much better again to learn on. I ride exclusively 1970s bikes and love them to death, but would never recommend them for a starter rider nowadays, because learning is much faster on a modern bike and the same applies for late 1980s bikes like that lovely Fantic. Surely there is something like a late 1990s Beta Techno available for equally low $$$. That Fantic would be priced higher here because they are a great bike for our air-cooled mono class, but unless there was that class, no-one would be riding one.

A funny sideline to this Beta thing is the name of the fabulous speedway motors named after James Arthur Prestwich. They were originally referred to as Jap motors, but after the Japanese started selling huge numbers of motorbikes, the James Arthur Prestwich brand was then referred to as J.A.P.

I was only joking and actually voted for BEE-TA, but I love hearing a Canadian friend call his bike BAY-TA

because of the initials origin, we should say b.e.t.a

our OSET 16 was well and truly worn out after 3 years. What sort of condition are they in?

They are not commonly seen in competition, probably due to their low production numbers, and high desirability as a display item. I've only ever ridden one, about 20 years ago, and my recollection is that it was not remarkable in any way apart from having a very interesting appearance due to the long shockie mount horns and the elaborate expansion chamber exhaust. It did have a heavy and high feeling about it (compared to the twinshock TY250 I was riding at the time). The OSSA was for sale at the time, and the test ride put me off buying it.

It is unclear which are you calling the main engine casings. There are two inner casings and two outer casings. Inner casings are also called crankcase halves or cankcases The casing that covers the magneto is usually called the magneto cover while Yamaha call it the LH outer casing.

There is nothing unique about the properties required for a condenser on an SWM trials bike. The capacitance required is the same as for any other set of ignition points that have faces of a similar diameter and run a similar gap. Because of this you can safely walk into an auto electrical shop and look at the range of "points/coil" condensers and select one that has a nice mounting lug. Where you might have trouble is finding a shop that actually sells condensers for points/coil ignitions, because for many years, cars, motorbikes, chainsaws, lawnmowers, and outboard motors have not used points/coil ignitions. The last one I bought went on my 1968 Bultaco and it was a condenser made for a 1960s Mercedes car engine. It was BOSCH brand and has a nice big lug and a long piece of cable

It's good to know which bike we are talking about now (TY175). The reason you have had the result that you have by reducing the preload spacer length is because TY175 springs have a special design feature. The coils are wound with a section a few inches long with almost no gap between the coils. This creates a dual rate spring. When the legs are fully extended in use, the section with the small gaps still has gaps, but as the forks compress, the coils in that section of the spring touch each other, which causes that section of the spring to effectively become a spacer. Because there are then less active coils in the spring, it has a higher spring rate for the remainder of the fork travel. By shortening the spacer from its standard length, you have increased the proportion of the fork travel that has the lower spring rate. This benefits heavy riders too, because they can fit a longer spacer and cause the higher spring rate to cut in at less compression of the forks. You can test for correct sag with you aboard and with all your weight on the pegs, and none on the bars. The forks should ideally be at 40% to 50% of their total travel, if you have the spring preload right for your weight.