feetupfun

DT250 sliders of the same era will probably work apart from the lack of the mudguard mounts that make the TY250 sliders unique. There are two different slider types on the TY250A. The earlier type has the drain screws on the sides and the later TY250A type has the drain screws at the rear of the sliders and are the same as the TY250 BCDE models fork sliders. Which side are you chasing?

Magneto side requires a puller for the magneto flywheel. The magneto flywheel will have ID on it so you will be able to buy the right puller. The drive side seal requires you to take the clutch off and to get to the clutch nut, you may need a clutch spring tool if you have the spring pins that have a cross-pin retainer. If you have threaded clutch spring posts then you wont need any special tool to get to the clutch nut. The clutch nut is 22mm (from memory) and requires a thin-wall socket because the nut is recessed. I machined the OD of a standard 22mm socket down for this. To unto the crankshaft drive sprocket nut it is helpful but not totally necessary to have a clutch holding tool. This sprocket is on a parallel shaft with key drive. It may need a puller to get it off. A standard industrial two leg or three leg puller will do for that. The clutch basket and crankshaft sprocket come off together with the primary chain in place. Bultaco clutch holding tool (helpful if the motor is out of the bike) Bultaco clutch spring tool (unlikely needed on a 199A) Thin wall 22mm socket (definite) Large two or three leg puller (maybe) Bultaco magneto flywheel puller (definite)

I do like how you think outside of the box. Please keep at it. Here is a story that might be of interest. At 64 and with lots of old injuries, I'm not looking to take big risks when riding trials, but for the past 15 years or so have had a thing about improving the setup and performance of my twinshock bikes, mainly to maximise how long I can keep riding trials for, because I get such a kick out of riding trials. Part of this bike improvement thing is that I have a few comp bikes and find that by riding the different bikes in the same sections on the same day, I can better work out how to improve them. Swapping bikes like this is usually detrimental to my score. It's also great fun riding different bikes through the same sections. It's not a big deal though and it wouldn't stop me from riding an event if I wasn't allowed to swap bikes. All I do is ask the event organiser in advance so I know how to approach the event. Sometimes it's no and sometimes it's yes. If they have concerns about fairness to other riders, I suggest that I'm happy to be taken out of the results if I swap bikes. In your case, you may be able to choose events that are more favourable for the sort of riding you want to do. Many clubs I'm familiar with run events where you can continue riding the sections after the event and also, depending on the observer and if there is a queue or not, are happy for you to continue in a section after having fived.

They are mechanically identical to the "Montesa Cota 200". If you search the Montesa forum using "Cota 200" you may find the information you seek.

Good to hear and welcome

Lots of people ride in competition trials events without using a scorecard. They just ride whatever line they want to challenge themselves with. Also lots of people enter the grade they feel comfortable riding and sometimes take a harder route to increase the challenge. I set lots of sections and my goal is to do it so that people can ride higher grade lines without going outside the gates for the grade they entered. Yes gate trials are great fun and they are also a competition. I love the mental aspect of gate trials in that the better you know your riding ability (and act on it when choosing gates), the higher you will place.

You've got me thinking. Doesn't the top triple clamp pull down against the adjusting nut?

Hi Dirk I'm in Gladstone, Queensland, Australia. We have an active old trials bike scene and have a great time. David

I don't know what tyres are available to you but if you can get a rear tube type IRC trials tyre it will be great on your TLR for trials. None of the other brands make tube type rear trials tyres. The Michelin rears are tubeless type and are more difficult to get to stay sitting on the bead seats on a tube type rim. The IRC is an amazingly grippy tyre like the Michelin. It is more sensitive to tyre pressure being too low than the Michelin as in the rear of the bike moves around if the pressure is too low. Where I live I can't get IRC rears for my twinshocks so I buy Michelin rears and trim the beads so they fit properly on my tube type rims.

I can advise you to say what country you want to register it in

To get milky oil out of the gearbox you drain the milky oil out the drain hole or by taking the clutch cover off and put dry oil in, go for a ride then drain that oil out then put dry oil in and go for another ride. Usually by then the oil is visually free of milkiness. If it is still a bit milky, drain it again and put in dry oil again. It's not a big deal/damaging/dangerous to ride with milky gearbox oil. The action of the clutch might be a little different to normal. The oil is designed to keep the water away from the metal bits by encapsulating the water as billions of microscopic globules. The water globules are why the oil looks milky to the naked eye.

$AU500 to $AU3000 depending on condition and location

Scorpa trials bikes originally had Rotax motors, then Yamaha motors, then they had financial problems and were bought out by Sherco. From then, they have had Sherco motors.

you can also use a DT175 A/B/C/D cylinder and head as a swap for TY125 cylinder and head and may be more easily found. The compression ratio is slightly higher than TY175 which some prefer anyway. Maybe say where you are located to assist you in your quest

I bought a Tubliss many years ago for the rear tyres on my trials twinshocks and ended up not even trying it because it was heavier than a tube. It's still on my shelf.

Depends on what you define "manufacture" and "in house" to mean. Yes. Some brands share engines with other brands. Current examples are Montesa/Honda and Sherco/Scorpa.

Yes something weird happened a few years ago that changed that. It previously showed if you were a financial supporter of Trials Central or not. Now we are all just Newbies!

In Australia, riding Motorcycling Australia sanctioned trials competition events, helmets are required to meet the same standards acceptable for on-road motorcycle riding, which in Australia includes helmets made to European standards, Australian standards and the popular USA standards Snell and DOT. There are helmets available that sit on the top of your head that are legal on Australian roads and they would therefore be legal for use in MA trials competition. Here is an example of such a helmet https://www.easyr.com.au/m2r-rebel-shorty-helmet-w-quick-release-matte-blac I wear a normal trials competition helmet because I think they are a good balance of protection vs comfort vs ergonomics.

Modern premix and injection two stroke oils for road use are designed to be "low smoke" to avoid making visible emissions and they achieve this by resisting burning during combustion of the fuel, but the penalty paid is that they condense/accumulate within the exhaust system as a gooey liquid. If the fuel/air mixture is well managed on your Alpina and you run a modern premix oil at 40 to 1 or 50 to 1, the exhaust gases will be invisible. If you want to get the best fuel/air mixture control, run with a new modern carby jetted correctly. I run a 26mm OKO from Mid Atlantic Trials on my Alpina and it runs super sweet with perfect jetting straight out of the box.

Further to what Woody said, having just converted my series 1 (1968) model 49 to having the later type magneto cover, I found that not all the later clutch cover types (with an adjusting plug) provided enough side clearance for the clutch spring adjusting nuts. I was just about at the point of replacing the clutch hub with one with shorter clutch spring pins, when I found a clutch cover that was the same shape inside as the original 1968 type clutch cover except that it had a pushrod adjustment plug in it. My point is don't assume that a later (boot-heel shape) clutch cover will necessarily fit over the clutch spring retainers in your Lobito. It has a better chance of fitting if you have the pin type clutch spring retainers. I found the clutch action with the original worm drive actuator was quite good (with aftermarket clutch plates and just enough spring preload). I changed my magneto cover to the later type so I could fit the model 49 motor in a later model frame with side frame rails under the motor. With the clutch cable retainer underneath, it interferes with the left side lower frame rail on the later Sherpa T/Alpina frames.

Judging how much oomph for obstacles is a skill that comes with practice, no matter if it's a 125 or a bigger engine. The concept of riding a 125 to start with is that the relative lack of power helps you to more quickly learn good riding technique. As for jumping up things, it is safest to initially "over oomph" things then reduce the "over oomph" progressively until you oomph "just enough".

Think about what happens as the forks extend. Those little springs cushion the end of the fork extension travel. They are important when riding up steep hills.

pretty sure the standard needle nowadays is rubber-tipped https://amalcarb.co.uk/shop

No argument about why two strokes need crankcase seals but we are not talking about crankcase seals, we are talking about seals for the internal parts of the crankshaft main bearings. Rubber - sealed bearings are used to help the bearings last longer in motors that have poor ventilation/lubrication of the crankshaft main bearings.