I’m rebuilding a Beamish Suzuki and going Alloy rims with SS spokes, I’m going to trial it, I’ve done older stuff for show and have used Stainless Rims which are nice and shiny and don’t tend to rust like the chrome option.
I haven't heard of trials bike stainless steel rims previously. Where did you source them from?
The Ty250 I found included an extra engine. It looks like the one still on the frame except the head has radial fins. I suppose it's a 250 from another Yamaha 250?
It looks like what I see listed on eBay as a DT250 or YZ250.
What does the rest of the extra motor look like? The DT250 radial fin head motor looks quite different to TY250 motor in many ways. Shape of engine covers, location of kickstart shaft, length of motor. It's a popular thing to fit the DT250 radial fin head to TY250 twinshock motors.
Can anyone shed light on the frame numbers below and how to work it out is the 19 meaning 1970's the MO standing for Montesa and 252 mean its the 252nd bike made...
19MO252
* Can't work out is the O letter O or is it the number 0 ??
the 19M means Cota 172. The rest is the production number
Hi, final had time over Christmas to spend time with the Cota. Everything including carb and motor have been stripped and replaced with new parts. However, there seems to be no fuel getting through. Good spark and compression, but not the slightest glint of it starting. Any ideas?
I saw a XISPA being ridden in a trial when they were first imported into Australia, by a person who I think was the importer. I'm thinking it was about 2010.
Hello to who ever reads this. As title above i have just fitted one of these clutches to my bike and though has any one used the 1 2 3 adjustment on these. I have just used number one and fitted the cover and before i fill up with new oil wondered about these adjustments. Having to drain the new oil and take off the cover and then have a chance of damaging the gasket for no gain is a no no ergo why i thought i would ask on here. Thank you.
You can usually lean bikes on their side to work on the clutch without draining the oil
Have this old bultaco not sure if it a sherpa t 350 or what the year is. Or the value. Any help is appreciated jm-15901369
Model 159 is a 325 Sherpa T from the mid 1970s. Where located? Does it run? When was it last run? What is its riding/maintenance/rebuild history? Front tyre looks like a 1970s Pirelli. Shocks look like original style Betors. These things make it look like it might have sat unused somewhere for a long time
If you're worried and want to check it out, measure what temperature it is running at. A thermal camera is great for this.
If the cooling fan duty cycle is more than about 50%, then I would be checking coolant level, restrictions to airflow through the radiator and if the fan is running the right direction.
There is no one on the forum who understands the carburetor?🥺
Your photo of the inverted carburetor shows that you have omitted to fit a gasket/copper washer under the float valve seat/body. This omission is a possible cause for the float bowl overflowing
In late 2023, I investigated a hot running issue with a friend's low hours 2022 TRS 300. It ran poorly when trail-ridden once warmed up.
I found some things wrong.
1 the coolant level was very low. From memory it took something like 300 ml to get the level up where the book says.
2. The fuel filter inside the fuel tank was restricted by debris.
3. There was way too much sooty carbon on the piston crown and inside the head for the hours it had run.
4. I found something that I don't know is wrong or not, but seemed odd to me. It had both a resistor spark plug and a resistor spark plug cap.
5. The reeds had wear marks from touching the open stops.
I found out that the owner had been using Castrol 747 premix oil (the one with some castor oil in it).
I de-coked it.
I cleared the fuel flow restriction.
I fitted a non-resistor spark plug.
The owner then ran it on semi-synthetic premix oil.
It ran fine.
The reeds are going to be replaced soon.
I suspect the running issue was being caused by the engine running hot due to lack of coolant, float bowl level going low due to fuel filter restricted and too-high compression ratio due to carbon build-up.
For flat turns, lean it over. Counterbalance the bike weight with your body so you can ride very slowly. Try it stationary to start with. This trains your brain.
Control speed in the turn using the rear brake working against steady throttle.
If you want to learn to do turns with the front tyre off the ground, one way is to practice turning slowly on steeper and steeper slopes (going up to going down turns). This gets you accustomed to riding turns with little/no weight on the front tyre.
Say you were just getting started in Trials (me), but also did adventure trips in the summer. I think these Leatt HydraDri 7.5 boots might work well for both, thoughts from the group?https://www.advrider.com/leatt-hydradri-7-5-boots/
My other boots are very stiff, heavy motocross style (Astar Tech 8).
After a chat with In Motion and a few days of trying the Web to source specific engine parts, including a Spanish vender, the spares situation is worse than I thought.
I run and ran more than a few classic bikes and cars, some of which are fairly eccentric, but never failed to find a lead on parts, until now.
Although, these Cota 200s are well thought of think I'll pass on this model, of only for the parts availability.
Maybe a useful heads up if anyone else looking at these, they are great value, but....😎
Reveal hidden contents
The lack of kickstart train parts for this bike and the other Montesa models based on the Cota 123 (Cota 172/200/242) is well known. There have been batches of suitable parts made in different parts of the world over the years, usually by individuals who needed parts and had a batch made (France, Australia....) and sold off the rest. I haven't heard of anyone doing this recently. I wouldn't expect that the usual commercial suppliers would carry these parts for such a small market.
I don't know what changes happened recently, but i cannot access the site on any of my apple products, it says its not secure anymore, my laptop works, but not my phone or Ipad, same with my wifes.
My laptop opens the site but my AVG virus protection produces a warning each time I open Trials Central.
The warning message is "Dangerous webpage. Threat category: URL blacklist"
The Trials Central page continues to work normally apart from this AVG warning message
Standard TY250 twinshock head has a single central plug hole. None of the TY250 twinshock heads came standard with a decompressor or a hole for one. The first series of 434 TY250 cylinder has a boss on the front of the cylinder that would allow the use of the type of decompressor that Yamaha fitted to some bikes, that opens a small hole between the cylinder wall above the exhaust post into the exhaust duct.
There are plenty of other 250 Yamahas that have a head that will fit on the TY250 cylinder and have two plug holes. The bike your head came from could probably be identified using photos of the head.
Aftermarket Yamaha heads in the 1970s were made to look spectacularly different to OEM Yamaha heads in a bid to make it obvious visually that they are aftermarket.
As well as the gasket thickness, the new float may be slightly different shaped, causing the tickler to miss it.
I had the same issue with the tickler not pushing the float down on the same carby. I didn't pursue a solution because I didn't like the carby anyway and fitted an OKO
I put this in Beta as it mostly covers that brand but some feedback on other brands included. Its YT but audio only. Really interesting point about the 250cc standard versus factory models. Well worth 20 minutes of your day to listen to.
Yep, never torque a bolt with anti-seize on it. I already knew about that. I always torque "dry" bolts. Good video. I'm willing to bet that GG has a typo in their manual. Although, anything is possible and I am certainly no expert but, I would be surprised if they use lubricant when they assemble their wheels. Published torque specs are usually for dry threads. I don't know... Will be interesting to see what the dealer has to say.
Yes the trials bike manufacturers don't seem to lubricate anything properly when they put the bikes together. People either pull their new bike apart and lube things properly, or replace the rusty and seized parts when they fail. In my experience the steering head bearings, swing-arm and shock link bearings last about one season unless lubricated post-purchase. Many people also lube the spoke threads as part of their new bike ride preparation.
If you haven't pulled a Montesa cylinder off before, you may not know that you will need an (uncommon size) 7mm hex drive tool for the (recessed) cylinder nuts.
If the rings are stuck, they may still be fine after cleaning out the ring grooves and the rings.
The D slide OKO provides faster response in both directions than any round slide carby.
Venhill and others make suitable throttle cable kits.
Yes different carbies require different length inner cables, unless you are very lucky.
The important Teikei carby parts for the carby that came on the TY250A have been unobtainable for many years.
The Domino twistgrip is a good thing. I have broken many AMAL T200 twistgrip cable attachments in crashes. The Domino is more crash-resistant and is lighter and you have a choice of pulley sizes. The Yamaha TY250A and the later TY250 twistgrips are also easily broken and the cable loop catches on things.
Restoring my Whitehawk TY175 for the second time in 25 years, but this time i want to smarten it up with new stickers. Does anyone out there know where i can get a set please?
Wheels for pre 65 Trials
in Classic Trials
Posted
I haven't heard of trials bike stainless steel rims previously. Where did you source them from?