dadof2

What makes you so sure the bike is not running rich?

Soften the old paint with paint stripper and scrape as much of it off as you can, this greatly reduces sand blasting time. I sand blast with dry building sand (the stuff used for infilling block paving). Its cheaper and softer than blasting grit, removes rust and paint OK without taking off too much metal. As soon as blasting is coat with aerosol etch primer (One £7 tin easily does a whole frame). Leave to cure thoroughly for several days. Then (spraygun) 2 coats of 2 pack primer filler (Upol) lightly sanding in between if necessary. Then (spraygun) basecoat followed by either ready mixed or two pack clear lacquer. The above paint system is tough, long lasting and easily touched in. Keep the coats thin where bolts go in and thicker where your legs rub.

The chances of sooting of the spark plug being exhaust related are very slim. Sooting plugs (assuming they are correct grade) is nearly always result of mixture (fuel:air ratio) too rich, ignition fault or gearbox oil leaking into crankcase. Back to the reliability topic. I have over many years trialling only ever retired once due to a bike fault (gear dog broke on well used 348 montesa). My other retirements have been: Broken handlebars (twice), water flooded (twice), broken rear sprocket, broken / damaged chain & or tensioner (twice), bent rear shock (on a twinshock) and footrest knocked off. Some of the apparent unreliability of modern bikes is probably due to the owners lack of mechanical experience. When I started trialling I had already had old motorbikes for several years and also had to regularly maintain my car, as did my father, brothers and friends. Nowadays people are generally get far less exposure to preventive maintenance and having to fix things.

From Jennings "the results can be given in a single, brief sentence: "Engine output and piston cleanness improves as premix oil content is increased." The above is a point I have made several times on this forum only to be criticised by quite a few. Graham Bell (another well renowned tuner) also favours a rich oil to fuel ratio. The proper answer for trials bikes is a pumped oil system like the early TY Yams had. This gives the near correct ratio for all running conditions, pre mix never can.

With one or two exceptions overall I think bikes are not significantly more or less reliable than they were. However because more recent bikes are more complex they are more difficult to diagnose and fix "in the field" than the older bikes. Modern bikes also need more maintenance. The peak of reliability was probably the TY monoshocks. MX bikes are similar in that the 2 stokes of the late 1980s and 1990s were more reliable and easier to fix than the 4Ts that followed.

Before I buy any product that has the potential to break down I try check out reliability record. I also check out spare parts availability and prices. In the case of something with EFI I would also check out the availability and price of diagnostics information and kit. If not available or unreasonably expensive then I would not buy a product dependant on them.

Count yourself lucky that this was brought to your attention in time for you to sort it out. Your trials bike is a motor vehicle even if not used on the road. Even the theft of a minor item (non motor vehicle) can affect other premiums. You are now in the unfortunate (and possibly very costly) position of having an insurance policy "voided" as a result of non disclosure. You need to contact the insurance ombudsman to try to get this corrected. Until you get written confirmation that what you have done does not constitute non disclosure, you need to advise all of your present and future insurers of the situation and how it has arisen. If you do not you could be committing fraud - which can result in jail.

Before slanging someone off perhaps you should look up the difference between brittle and ductile fractures. Many aftermarket footrests are narrower along the bolt axis than standard footrests. People then nip the bolt up to remove slack stressing the mounts in a way the designer did not intend. Loop type footrests flex quite a lut back to front cushioning the force transmitted to the frame. Stronger aftermarket footrests flex much less and more force is transmitted to the mount / frame. The brake in the photos is almost certainly due to brittleness and an impact trying to push the footrest forwards, not rider weight.

I have tried both extra base and head gaskets on various bikes both to soften the power characteristics and ease starting. The effect on the power tends to be greater than the reduction in kicking effort. Bearing in mind you often have to start a trials bike in less than ideal positions, a change of bike may be the best option.

Is not the Ho Chi Min Motor Show in Vietnam? Why oh why post such a silly post?

Looking at the colour and finish of the break (a very fine light grey structure) this indicates rapid cooling after the previous weld. MIG welding is minimum heat input followed by rapid cooling. Also there are many different "steel" MIG wires. Much of the cheaper stuff as used for garage work and light fabrication does not give a tough weld. Far better to use TIG with a tough dissimilar metal type filler. Two reasons why non standard footrests can cause breakage are the size of the mounting can stress the frame and the aftermarket footrests can be less flexible, transmitting more stress to the frame.

You can greatly extend the life of RS bearings. Flick out the seal with a very fine screwdriver, clean the bearing with 2T mix, dry then repack with good grease and push the seal back on.

TIG weldt it with Armoid or 317L filler

Probably at least partially right however it is also the case that bikes being illegally used have a significantly higher proportion of being illegally acquired than bikes being legally used. My impression is that each year the organisers do more to try and provide parking. Something I would like to see is a bit more tape to keep spectators back from the sections but then again the organisers have enough to do already, bit more sense from some spectators would help.

I have had several bikes with air forks or valves in caps. Some of the forks it to adjust springing (5 to 15 PSI). Others its just to let pressure build up out. I find that having air or springs in the forks makes no difference to the way I get on the bike, I just swing my leg over on either type.

I can generally manage by holding the rings in place with mu fingers in the transfer slots in the "liner". Another method is to tie the rings tightly in place with fine copper wire Then seal the rings into the grooves about 30mm either side of the locating peg with candle wax melted well into the ring and groove. Remove the wire, scape off the excess wax. Once the barrel is fastened down heat the top of the piston to allow the rings to spring out. The rest of the wax soon burns off. If you are fitting new rings always put them into the barrel and check the end gap first.

Using fuels high in ethanol will speed this corrosion especially if bike is left stood for extended periods with tank part full

When I started motorcycle riding full face helmets were far from universally worn, my first road bike helmet was open face with full length visor. Many MXers were still wearing open face and there were no bar pads so as someone posted earlier plenty of work for the dentist. On trials without road work you could still ride without a helmet and many did on hot days. I can't remember the make but my first trials helmet was one of those that only protected the upper parts of the head, same as worn by Martin Lampkin etc. I am completely comfortable in a full face helmet on a road bike or one with a chin piece on MX, but when it comes to slow work on a trials bike or enduro I find the chin piece distracting and claustrophobic. In theory a chin piece should increase safety but that does not always follow. In MX the top edge of a chin piece (if goggles are removed due to loss of vision) can defect pebbles and dirt that would have struct the lower face, up into the eyes. In trials where no eye protection is worn the same goes for a handlebar end or lever, the chin piece could deflect it up into the eye area. I remember a work colleague many years ago removing the circlip that held in a fork seal. He had the slider in a vice and was pulling upwards hard with both hands on the circlip pliers. The pliers slipped and he broke several front teeth with the plier handles. I have never seen such serious mouth injuries at a trial.

You need a T handle hex wrench that is larger than the socket in the sleeve nut. Carefully grind it to reduce the across flats dimension so it will not quite fit into the sleeve nut, a slight taper on the last 2 mm of the flats gives an indication of nut size. When it is ground to slightly oversize hammer it into the sleeve nut. Then get someone to apply quite a bit of torque on the T wrench with both hands whilst you strike the end with a copper hammer.

Comma Oil, VAG - Volkswagen Audi Group. There will be other makes as well. These red types tend to react badly with other antifreeze. Flush it all out and replace with ordinary ethylene glycol, specialist motorcycle coolant or universal OAT (orange). I get OAT from Smith and Allan - Occasional Scott sponsors

Exit it high up with the end facing down and cut off at a slant so drips run off. Exit needs to be where washing won't make water get into it.

How hard to kickstart maybe more of an issue than how much power.

Eddy Dobson?

Its some time since I had a Rev 3 apart and have never been into this part of an Evo but I guess the end of this screw fits into a slot in the kickstart mechanism. You might be able to get it back in by moving the kickstart a little but it is probable you will have to take the case off and remove the return spring before you can get it to line up.

Perhaps the most emotive engine sound is that of a B17. First it whines as if it does not want to go, almost as if it know what lays ahead, then an odd cylinder or two give a pop and a puff of smoke, it whines some more, then more reluctant pops and smoke as it come to life before the misfires finally cease, the smoke clears and it settles down to a steady beat, purposeful and ready for the task ahead. This is not just an engine for a bit of fun on a Sunday, it is an engine that is part of life and death, an engine that will take many to a fiery end, and return others to contemplate their likely destiny.