tony283

With the bash plate off directly under the kickstart shaft there is a 17mm Hex head bolt.... DO NOT remove, the drain bolt is further in and should be a flat allen bolt. Tony

You don't say what model this is. If its a TY250A then the oil is injected into the barrel directly on the right hand side. A simple bolt in this hole will fix the problem. If it is a later model then the oil was injected into the front of the carb and you will need a small blanking rubbber over this inlet. Other problems could be the needle clip position and the size of the main jet. Use a 150-160 main jet and set the needle clip on the central position. The timing on ALL of these TY's is a fixed stator plate so unless someone had modified it this will not move. Make sure you are using the correct plug (NGK B7ES) and set the gap to 22 thou and make sure the points are 15 thou. Tony

For those of you who enjoy the Vintage scene, 3 days of reports and pictures from CASPER are now up on my "blog" Tony

For those of you who enjoyed the previous articles here is another on how to ride your Jumbo...... "Mahout Trials Training Camp"...... just hit the "Blog" button Tony

For those of you out there about to do oil changes, or have recently done one, you might enjoy these Jumbo sagas on my blog. "Elephant Tales", "Jumbo Bwana" and "The Clockwork Elephant" enjoy! Tony

BLACK =SLOW WHITE =FAST Tony

Can anybody tell me the correct length of the fork springs as fitted to the 38mm Betors on a SWM Jumbo ? Tony

All the news from the preview to 2 days of Vintage Trials at Tucker Ranch Cotopaxi CO. 40 riders each day. 3 reports available now on my "Blog" Tony

The Ty250A was the first bike in the Trials world to be fitted with the reed valve, and bearing in mind mine was the first pre-production bike to hit the UK shoreline in time for the 1974 Scottish. Nobody was over enthusiastic with the "snappyness" to begin with as we were all used to Montesas and Bultacos and the difference on a standard "down the hill, round the tree, up the hill type section" was very noticeable as you found yourself up the bank in a nano second and going to fast to make any turn. The later engines were much softer off the bottom end and perhaps more manageable for most clubmen. Of course now, with our classic "round the tight turn into an 18 step" the snap and zip of the 250A motor are perhaps preferred especially if you come down 1 tooth on the engine sprocket. Tony

The 250A is much "snappier" and through the progression to the full width barrel the response was made much softer in the 250C/D with different porting. If you have tried changing the carbs then I very much doubt that the C model has been increased in engine size as although they will both run on a 35 pilot the bigger 300 or 320 Majesty engine requires a HUGE main jet going up from 150/160 on the standard to 290 main on the 320 engine. Tony

No, normally there will be awards for Winner, Runner Up maybe Third then maybe best engine capacities and then a % of finishers. The class awards are usually stated in the regs and are First Class Awards for the first 10% of finishers then Second Class Awards for the next 10% of finishers. Tony

Better save up for a stator plate as well if you are seriously thinking of riding it like that in a trial!!! Tony

Pretty though it maybe, I assume the flywheel cover is a joke and you have a good one to use? Tony

Original cables are still available here in USA. Advantage over the others are that they fit! + they have the lever cover included in the price. Front brake cables as well, as the Venhill in the past does not have the anchor attachment, and will not fit the Ty250A. Available from Speed & Sport in PA. Tony

Yes, it is a 348 but you have a lot of rectification required!! The coil has been fitted backwards which is why it touched the exhaust. Like wise the front mudguard bracket is on backwards,and that has meant the mudguard touched the exhaust as well. The correct position with the bracket reversed will put the brake cable in the correct alignment. Also the brake anchor is incorrect and you will need to find another. The Carb looks like Mikuni whereas the original was an Amal. Kickstart needs to be replaced as does the engine sprocket and no doubt the rear and chain as well. Rear brake? Adjustment looks way too far forward on the actuator arm. Footrest positions are normal but to may want to lower them and put them further back. The two plugs you have are not normal as the lower one on the side is where the decompressor should be or a blanking plug fitted. Rear shocks look longer than standard ? Do check the carb to engine rubber inlet as they perish and crack. Best of luck Tony

There are many machines that are Pre 65 eligible that never ever had lower frame rails, The Enfield and Ariel are just 2 that come to mind. Tony

Gordo, I've run both Dunlops and IRCs which arrived, like yours tubeless when tubed type had been ordered. As long as your security bolts are good you won't have a problem. Tony

Simple answer No. The seat is slightly bigger and the two frames are different . It can be made to fit 175-250 Tony

All of what you mention is normal! For best performance in modern day sections I would advise coming down to a 12T engine sprocket. Do not be tempted to go to 11. Tony

Squid, The 125's do have a tendency to "spot" with little oil/fuel marks spraying on the rear mudguard whereas the 175/250 tailpipe is different. You could be getting too much mix into the engine through over running with the choke on or the float valve could be sticking. If the float valve is stuck, quite a common problem, you can remedy this with a very light emery cloth. Take the carb off yet again, remove the float bowl and this time push out the little brass rod that holds the floats in place. The valve should now fall into the palm of your hand! It has a sharp spherical point on the upper end and often gets corroded allowing fuel to weep into the bowl. A quick polish with the emery will stop this. When put back together push the floats up and then release to see if the valve is opening and closing smoothly. Tony

Genuine OEM pistons, rings, gudgeon pin and clips all available up to 4th oversize from Speed & Sport in PA, usually with a good discount. Shipping would be around 20 quid. Tony

Squid , With the carb off the bike, float bowl removed, slide cable etc out ...... the center hole in the body is the Main, about a 1/4 inch behind the main there is the pilot, and unscrewed from the bowl side. When you look through the orifices the main will most likely be clear and you will see daylight. The pilot may not be so clear and may appear to have an "S" in it. A small bladed screwdriver is required to remove the pilot. Take care as it is brass and you can easily turn the top off if it is stuck! The numbers (size) are on the jet and with old age can be hard to see. Tony

Squid, UNDER NO CIRCUMSTANCES WHATSOVER ever use any silicone sealant anywhere near a carb!!!!!! Fit the correct gasket and do not over tighten! Undo it one more time, make sure it is seated correctly, refit the bowl, soft tap with ruber hammer and screw it up. Tony

Wacking is NOT the answer! Best bet is to take to someone who has HEAT and bend it back where it should be. Another way is to take a long pipe over the stand, with the bike on its side, and gently alter the angle with some long leverage. You might also be interested to read my article on carbs on today's blog. Tony

Right hand side of headstock and will start with 493- in your case and most likely the next number will be a 2. The same numbers should appear on the right side engine case inner just in front of the kickstart. Tony