woody

They are different designs but probably achieve the same result. The Bultaco UK one is much easier to fit as it has a fixed stator position and then a three way adjustment for static timing position. The Electrex ignition sounds very time consuming from the advice given above. Rex Caunt also does one (possibly the same as the Bultaco UK ignition)

If it is still running the original Amal carb, the slide/body may be worn, even if it looks ok. It would be fortunate now to still have an original Amal in good working order and without wear, given the hours it will have done. May be worth trying a new slide. If the body isn't too worn it should stop it (if that is the problem of course, but worth a try for the cost of a slide)

Pictures below from the later bike showing the cable run and mounting points. The brake pedal is one I made to try out to work with lowered footrests. I don't like the original anyway as the pull seems to lack feel and it is the wrong shape for the lowered footrests. I've ridden with this pedal a few times now and it works fine so I'll tidy it up. You could make a pedal mount easy enough if you have a lathe, or someone to do it for you. Turn a piece of solid bar to the required diameter, drill and thread it at one end, drill a hole in ths swingarm plate in the required position and bolt it to the frame - bolt going in from behind the frame. I don't know what hole is already drilled by your footrest hanger but the 159 doesn't normally have one I don't think. If it is that close to the footrest it may not give the required leverage for effective brake operation

As per above post there is no accurate time period for how long a piston will last. Back in 2000, I bought a new Yamaha YZ426 for enduros. The manufacturer's recommendation was to replace the piston every 3 races (motocross) The bike was used regularly for over 3 years in many many enduro and H&H events, ridden hard, regular oil changes but never abused. Also used it on the road with supermoto wheels and did the Weston beach race on it. The bike was still on its original piston and rings when I sold it and would still wheely off the throttle in 5th. You don't say why you're concerned about the piston. If it's because of performance and you're not sure how it should run, as mentioned above get someone else to try it who has experience of them if possible. It could appear to lack power depending how it is tuned, The rotax engine can be fitted with a flywheel weight - easily checkable by removing the ignition cover as it is held onto the flywheel by 3 bolts. If one is fitted it will slow throttle response. Also, the disc timing can affect power delivery I believe so something else to look at, also ignition timing, points gap and state of the carb. If you're just wondering as a matter of course how often it should be changed, there is no specific answer. Just change it when it rattles so much that you can't put up with it any more...

Black to the HT coil.

It's more symtomatic of modern trials rather than how no stop used to be years ago. There was no trick riding then so issues like Sam's ride didn't arise. Listen to the applause from people watching when he rides the section. They all think it merits a clean but really it is a 5 as it's against the rules to gain advantage. Imagine though, what may have happened had the observer given 5 to the knowledge of rider and spectators in a situation like that. Some riders (and spectators/minders) could react very badly, the observer can take the easy way out (which is understandable in not wanting a confrontation) The rider in instances like this probably feels they kept on the move. The bike itself may be moving, but not forwards. The perception from on the bike is different from those watching in respect of what is actually happening. This happens in almost all modern no-stop trials I've ridden in, so there is no question of singling out observing decisions at the Colmore

Video 1, Sam Connor, a definite stop. The stop is used to reposition the back wheel. Foward motion has ceased under the control of the rider to move the back wheel in order to reposition the bike to get a better line than you could riding it non stop, possiby saving a dab on the turn. It's a 5 for stopping. Video 2 suitably demonstrates what a boring pain in the a*** stop allowed can be, especially if you're in the queue of riders on a tight time limit waiting for your go. In the other video of Maria Conway, it is a 5 as a result of a mistake. The rider has lost momentary control and slammed into the opposite bank and stopped. 5 marks. Harsh maybe but that's the no stop rule, you pay more for mistakes. If a tennis player twitches slightly when playing a shot which results in the ball going 1mm over the line instead of in, they pay for the mistake. Why is trials viewed differently by some people. In the video of Emma Bristow on the same section as Sam, it's very close to a stop as well.

A few have surfaced recently - good bikes, the 320 Hiro is a very good motor. Don't know whether the TX300 came as just 280cc or 240cc as well

There were three at the trial, all 320 Hiros. Quite a rare bike as not many came into the UK. Even rarer, the TX300 Rotax powered last twinshock model, maybe only 2 or 3 of those here

Yes, the trial involves a lot of roadwork, same laws apply as a road trial here

They are rear shocks, various types - single spring, multiple springs, fixed or adjustable damping. The front fork kits consist of a new progressive spring, internal adjustable spacer and the Magical fork cap with adjustable preload. There is no valving kit for the damping.

No problem, just apply for the V5 using Form V62 I think (from memory as the DVLA website is down at the moment) It will cost

Don't follow you, if you have V5 it is road registered already

Just ran last year's quote again on Go Compare. Cheapest is E-Van but it has gone up from

I've been with them for a few years and last year's quote was ridiculous, increased by about

Hi Simon, I remember the bike well then, yes, as I had a ride on it in France and remember it being like no other 340 I had ridden. I remember the steering was done but the suspension worked well too, better than as is usual and the motor was very smooth carburation and torquey. I'm sure I tried to prise it off you at some stage. When I read your original post I did wonder if it was that bike. If I remember it well enough, it doesn't need much doing in terms of improvement.

I didn't mean there was no need to do what you have done. I hadn't actually seen your post when I wrote mine. It is just that I have read before that the Bultaco airbox is inefficient, whereas in actual use I have found them ok.

The standard clutch can work well by lengthening the arm a bit (don't have an exact measurment but say about 10 - 15mm as a starter) I use Barnett plates and have backed off the tension on the springs as the Barnett friction material has more bite (according to their website) To do this you have to reduce the length of the nuts that tension the springs because if you don't they will hit the inside of the casing if they are more than about 5 turns out from fully compressed. How many turns out you have them is trial and error to find the point where the clutch doesn't slip. Fit a low friction cable. With a bit of time it's possible to get a one finger clutch. This can also be achieved with the standard plates (which are used by Puma and Vasquez) They also drill the fingers on the basket to let oil flow from the plates easier (personally I have no idea if this is necessary or makes any improvment) I've no idea what the airbox improvments sre. There is nothing wrong with the standard 340 airbox. Mine has a ported barrel (Vasquez but I've no idea what's been done) and the bike will rev like hell using the standard airbox, there is no problem with air supply. Carb is a Dellorto, 28mm I think. Rear silencer can have the baffles removed and replaced by continuing the perforated tube at the inlet end of the silencer right through to the outlet and having a single pipe outlet, like the old banana silencer from around 1974 bikes. Repack both middle and rear silencers. Mine has the steering angle pulled in but standard swingarm. You can only pull the wheel in so far on the Sherpa as the front mudguard will hit the frame so the wheelbase isn't an issue or too short. Grip is not a problem with the standard swingarm and steeper steering. Best solution for grip is well set up rear shocks and a good tyre. I really wouldn't bother with the swingarm, unless you've found a way of really steepening the steering and ended up with a 50" wheelbase. I have Magical rear shocks, very pleased with them. Front susepnsion has the Magical spring kit with standard damping. It's transformed it. On the clutch you can fit the weight from the 250 and also the ignition flywheel from the 250 which will save some kg but the engine will stall very easy at low revs so you need to use the clutch more. The engine will also respond much quicker, maybe too quick. EDIT - 250 ignition flywheel if you have Femsa. I forgot some 340 Sherpas had Motoplat.

I always thought the Yam frame rode nicer than the Godden frame anyway. The Godden frame on its own was a heavy lump and the Godden bike was front heavy. The Yam frame was quite light and that bike felt more nimble and flickable. I'd prefer the Yam framed Majesty from the two.

Headstock looks all wrong for a later Bult frame (or any other) and swingarm looks early model. Could be a later Miller frame or Bult frame from around '76 looking at the frame around the swingarm pivot. Swingarm pivot is moved forward. Slide through lever to the kickstart as well instead of the swivel. They were trick in the day. I had one of those on my first Sherpa, a model 80, except the sliding bar was missing. I had to kick it on just the arm instead.

Oh Christ, that's one of the funniest replies I've seen to any post for a long time

Madness - I think..?? As I said in another topic, twinshock prices are crazy and bear no logic. They're worth what someone will pay I guess but that will need another

I have Magical fork spring kit in my 340 and it works very well with 10W oil about 180cc The Bultaco will cope with the Sammy Miller sections no problem, there is no need to modify the head angle. Agreed it improves steering but for that series it isn't necessary, there is nothing it won't steer around. You could always fit 360mm shocks which is what I did on an M49 I rode in the series a few years ago.If yours is the series 2 M91 they steer pretty well anyway. I haven't a clue about Mikuni jetting so can't help with that. I did fit an OKO to an M92 and it only needed minor change to main and pilot jets, it ran well straight out of the box. Skimming the flywheel is personal choice but again, there is nothing that a standard 250 motor can't cope with in the Miller series, it's a good strong torquey motor. My M49 had no problems. With taking weight off the flywheel I'd be more worried about losing low end plonk than anything else as the engine will stall easier meaning you'll be relying on the clutch more at slow speeds. The Bultos will lug right down to nothing with the standard weights. As a purely personal opinion, the best prep you could give the bike for that series is to ensure that the motor is set up right, carburation is correct and exhaust functioning properly. Good tyres. Get the front and rear suspension working correctly and get the riding position comfortable with bars and footrest position. If all that is correct it will make a marked difference on how the bike performs. Ride a few events with it and if you still feel it is necessary move onto the steering and flywheel mods, but I'm confident you'll find it isn't worth it. I've ridden both the M49 and KT250 in the Miller rounds hard route, they are similar handling bikes and both cope no problem.

Good fun but it proves nothing as there is actually no point to prove. A trials bike will always be quicker around those micky-mouse indoor enduro circuits. As Tim says, on a proper WEC enduro special stage the trials bike would be nowhere, the same as the enduro bike would barely get through the start gate of a WTC section (unless it was Grimbo on the Husaberg....) Have a look at this and imagine how far behind Knighter the trials bike would be at the end of the stage. http://www.youtube.com/user/renderwtal