mattylad

You could also put the entire system on the BBQ or a fire and heat it to burn out the gunk!

If you read french look at Mijossi.com which has an article to improve performance of a TY125 which also includes shortening the rear exhaust perforated tube or even better using the centre core from a TY250 which is significantly larger.

The DTMX uses different crankcases. The centres of the studs are different where it bolts to the cylinder. Be careful before you buy. Why not buy a TY175 cylinder on ebay uk, much cheaper than in France!!! Also look on the Mijossi.com site there is an article to improve power from a TY 125.

I'm going on holiday to Tenerife in mid february, anyone out there have a contact for clubs or riding schools etc. Many thanks

I spoke with Mick andrews a while ago and in his opinion reeds are not necessary. Although if you talk with Keith Horsman you get a different story. I have a few ex-works engines and they came with about half a dozen flywheels of different weights so that may be one way to go. Theres actually not much wrong with a well set-up standard engine in my opinion, it all depends what you are riding against. Here we have a pre 1978 class so youre not up against a Fantic for example. rex caunt sells some lighter clutch springs which help greatly.

Message for Andy T Did you make up the airbox from scratch or is it a modified version? Any help would be most welcome as your airbox looks about the most stylish i have seen in a long while. Cheers

I only grease part of the taper, the quality of the fit is too good (yam quality) You are probably correct about not greasing but you have problems getting the thing off again if you don't so the choice is yours. If it does fly off under load you have a long walk back but at least it is well contained. Ive been running mine for a year now in this condition without problems.

I also had one that was well and truely stuck, tapping, penetrating oil. swinging on the end of a torque wrench, nothing would shift it. Resorted to the "hot spanner", put on puller and heated the the magnto taper. It got b****y hot but sprung off with quite a bang! Luckily I caught it before it hit the floor. This is not the first time it has happened on a Yam so I lightly copper grease part of the taper to aid removal in future.

Lee, Thanks for your answer, indeed there is a C on the piston which was made for Fantic by Galardini (spelling) as both names are cast on the inside. At least I know it is a standard piston and not mucked about. Matt

I have stripped down the top end of a Fantic 245. If I buy new piston rings are they all one size? The barrel has C stamped into the top fin I assume this is the clearence code. The bore looks very clean without any marks so should be OK. The reed windows in the piston are just two small holes (approx 10 to 12mm) with a single hole high up just below the rings is this normal? What is the thickness of standard base gasket as the one I removed is very thick approx 1 mm. What is the method to ignition time the engine? Spark will kill a horse! What are the standard carb settings as mine has a Dellorto 55 slide, 98 main and 40 pilot jet. Any useful mods that can be done on these engines.

The lad lives up in Cockermouth, West Cumbria.

My nephew is mad keen on trials and is looking for his first bike. What would you recommend??

Bit serious this, at 47 I'm still glad to be breathing!!! As long as you can ride the rest is immaterial. Obviously fine dining and good wines has done nothing to harm my performance (if only). I admire your resolve.

"Incidentally if somebody turned up on one of the extremely rare Cheney monoshock cantelever Ossas they should ride as a monoshock also. A previous post mentioned "Evolution" well that bike is a perfect example of "Evolution" a converted monoshock is NOT." Given that the Cheney/Horsman/Ossa UK bikes were built in 1974 to 1979 or there abouts they are most certainly twinshock period. I can assure you that the rear cantilever suspension is no where near as sophisticated as a Yam mono so why would you peanalise them? They are more a historical quirk than a real threat to the winners podium.

The same Mr AC seems to make a habit of changing sections. We spent a couple of years in planning sections for a world round and on the day before you would not believe how many rocks were moved as the section was "too difficult", funnily enough AR and TB had already passeds the sections as fit for purpose!

Still think there is place for an "Evolution" class. All the modified bikes running against each other whilst the real twinshocks can play together.

Save a lot of time and mess and buy a WES tailpipe which is repackable. The middle box will almost certainly be blocked as well and this involves cutting and welding. Well worth the effort though!

New spokes can be bought try Nigel Birkett or JK Hirst.

Barnett make Kevlar clutch plates for the TLR which are the bees knees.

The reason the case breaks is that the clutch arm puts a trmendous pressure on the casing. If the bolts holding the case, especially the one behind the sproket the flex will break the alloy case. And yes they all can be welded and most are.

Thanks for the info.

I would like to give you my thoughts from a European perspective where I do most of my riding. Classic trials in Europe is for only classic bikes! Entries normally in the 50 to 80 rider range. Multi day event 200 to 300. Bikes are much less developed than in UK and the emphasis is on enjoyment!!! Sections are designed for older bikes with not too many tight turns. The rules are simple, aircooled twinshocks with drum brakes. Even the dreaded converted mono is thankfully not too common, these tend to be ridden by less able riders or ones who move up a class from their normal capabilities. The key is "honesty" to both yourself and fellow competitors! The social aspect is very important with beer and BBQ at the end of the day followed by the prize giving. Punchcards are used which of course means more observers. We also have either a pre 74 (France) or pre 78(rest of Europe) class with currently very stock bikes. This allows early spanish bikes to have a class of their own. i.e a 250 Bult is not competing against a SWM Jumbo or Fantic 240. I think it is the wrong way to go to allow old blokes on modern bikes to ride in the same event. Here the sections are made for old blokes on old bikes. I.e. no big steps. Have to say that all the bikes coming from UK are normally of a much higher (and more expensive) engineering standard than over here. E.g. tubeless rims are very rare! 300 quid rebuild is a non starter when you buy a S/H standard for 50. Don't know what the solution is but the 10,000 pound winner must be avoided. A way needs to be found of taking the cost aspect out of the twinshock scene other than that I am afraid you are right it will die for all but a dedicated few. Why not consider an "Evolution" class for everyone who doesnt want to ride a standard bike. here anything goes loadsamoney or converted mono could ride against each other. For the rest a standard twinshock class could be: stock frame (delugging, removing brackets for road gear, removal of under engine tubes all acceptable as these were common period mods)footrest and rear suspension mounting points could be modified (such as with stock Yams looking like Majesty) , fork diameter, stock yokes, and wheel hubs, with a standard wheelbase (within 25mm ???), swing arm could be changed. Engine must retain original crankcases, outer cases, cylinder and head. (The rest is hidden anyway so you would never confirm a modified porting for example). Carbs anything goes except fuel injection. Exhaust, airbox no restriction. Modifications should be based on improving reliability (ignitions) rather than increasing performance, as no one wants a long push home!!! Even these definitions allow significant scope for development without making the bikes overly expensive or performing so much better than "real standard" bikes. I still think that a good rider on a stock bike would come out on top, again I come back to one of my first points is that the rider needs to be "honest" to himself and abide by the spirit of whatever rules are introduced. After all it is only a sport

Could you please tell me if the 50 and 80 versions were the same bike with a cylinder change? Did they both run 21" front and 18" rear wheels? What was the seat height and wheelbase. How long were the front forks from centre of wheel spindle to top of stanchion? Any info gratefully received.

Where has Coudina gone he was on their stand at Cologne bike show last autum

http://www.r2wtrials.co.uk/html_files/bobwright.html Not much but all there is is on the fantic spares page.