dadof2

Swapping stator is obvious way to go. I don't know of anyone good at diagnostics in Wolverhampton area but if you contact http://www.picoauto.com/automotive-oscilloscope-guide/ or Frank Massey who is at Preston) they may be able to advise you of someone nearby.

Hi again Yes you need a clutch holding tool - cheap and quick on Ebay or a number of online suppliers Also you will need a flywheel holder and puller I think Sammy Miller does all 3 tools Crank cases pull apart easy enough

Axulsuv # 41. I rather like the golf courses in Florida - the ones with alligators in the streams - No stopping in there or you would get your leg chewed! I stand corrected but from what I remember Eddie Lejeune was a no stop rider, the time stop and hop really set in was just after Lejeune the Tierry Michaude / Jordi Tarras era when British WTC was held a Houghton tower in Lancashire.

http://www.trialspartsusa.com/electrical.html You should find a wiring diagram for your bike at the above. Gasgas change the system for 2006, the original being very poor - you can see its bound to fail if you see some of the internal connections. I was told the updated system needed a change of crank, making the parts bill in excess of £700 total. I would contact PVL and selettra ignitions direct to see what they can offer. I think there is a UK kart supplier where these can be obtained. Alternatively do a web search for Bradford rewinds.

09 is now 4 years old and about time for some corrosion to have built up in master cylinder. A complete strip and thorough lean including polishing the cyliner bore with fine wet and dry will probably cure it. Check for leaks / cracks everywhere.

Intermittent starting which gets better with a hard kick suggests low compression or an ignition fault Where are you located in UK? I would expect the source coil on the stator to give in excess or 23 volts AC at 500 RPM. I would expect Ht voltage to be at least 7000V at 500 RPM. Any garage with a diagnostics oscilloscope should be able to check this out fairly easily for you. The waveforms and the duration are as important as the voltage. You can crudely check the source coil output with a digital multimeter whilst spinning the flywheel with an electric drill.

I check the squish without any gaskets and very little torque, head and barrel just nipped down. I use resin cored colder about 6mm long, one piece at inlet side, the other at exhaust side. I turn bike over slowly with spanner on flywheel nut. I then take gasket thicknesses into account when doing the squish calculation. I often make my own base gaskets from either proper gasket paper or serial packet card. I stick it tot the barrel with blue hylomar and put copasliip on the crankcase face. I often reuse head gaskets, I just clean the old ones and then coat them with a mix of thinners and hylomar.

Many years ago I used to run vegetable oil - shell sport R40 in my trials bike. I had to borrow some petrol with mineral oil in it. Bike ran fine. I also know of one bloke who put about 3 litres of contect duck oil in his tank. Remarkably the bike ran OK even though it stank a bit. the problems only seem to come when the fuel is left and it separates. Something people do not generally know is that you should not mix 2T oils or greases from different manufacturers or even different products from the same manufacturer. They may have different base and additive packages that can react rendering them useless as lubricants and even corrosive.

http://www.youtube.com/results?search_query=scott+trial+1974&oq=scott+trial+1974&gs_l=youtube.12...0.0.0.1641850.0.0.0.0.0.0.0.0..0.0...0.0...1ac..11.youtube. With just a week to go a look back to when men were men and bikes had decent fuel tanks. None er yer poncy hopping about stuff here!! Enjoy (oh my god thats poncy waiter talk)

Too much oil can cause pinking as pistonbroke says. Too little oil can also cause pinking because of raised piston temperatures. Your carburation need to be right whatever your fuel : oil ration. The next time your bike makes this noise pull the clutch in and stop the engine immediately. Check the plug colour. The nose insulator should be chocholate brown. Any lighter and your plug is too hot (wrong grade?) or your mixture is too weak - larger main jet needed. and maybe raise needle (lower clip). Also check float level.

Pinking is when the fuel air mix in the cylinder is ignited by something other than the spark plug. it causes a violent burn (putting it simply) which makes a rattling / chuckling sound. The exact sound is dependent on the make of bike, amount of engine wear and cause of pinking. Do not keep making your bike do it. Pinking will wreck little end, big end and main bearings and possibly hole the piston. Common causes are retarded timing, advanced timing, insufficient squish clearance, coke in the cylinder, overheating, weak fuel air mix and poor fuel. If you are using ordinary petrol try BP ultimate or the better grade of shell or add an octane booster to your fuel. Edit - I once bought unbranded petrol and all 3 of us who used it suffered pinking, switched back to Texaco and pinking disappeared.

Gas gas did themselves no favors by not thoroughly investigating this and rectifying this at the first sign of trouble. The next time a GG dealer complains about lack of sales (and several are) tell them to make bikes with kickstarts, gearboxes and brakes that work. A few years ago a bloke I know had the ignition on his GG 250 fail at just over a year old. GG UK could not care less and dealer from who he bought bike new charged well over £300 to fix it., I still have the bits and all it was was a faulty trigger coil. Complete stator and flywheel had to be replaced as GG only supplied them as complete set.

What sort of Castrol? Unless it R (vegetable oil) it will mix but the sooner you use the mixed tank the better. You can mix near anything, synthetic, mineral and vegetable so long as you don't leave them unused long enough to settle out.

Only spark plugs I have had fail are Champion, but twice in over 40 years is still pretty reliable

Is it pinking Can you get someone who knows what pinking sounds like to try it?

See if your radiator tubes are clogged. I do not know anything that shifts this crud for certain. Try radflush. Run the bike with a piece of calgon (dish washer cleaner) in the system and just use water - no antifreeze. Change this regularly Try Clarkes aluminium cleaner (machine mart). Just a guess but maybe mix it 1 part cleaner to 4 parts water. If you do this don't use antifreeze and flush the system thoroughly as soon as the bike cools.

A beta 50 should make reasonable power but any wear on any 50 has a disproportionately negative effect on performance. I would check the exhaust and exhaust port are not coke up. Take the barrel off and check for bore rings and piston wear. the ignition system can be weak and this reduces bottom end power. An iridium spark plug will help. Other than that make sure the air filter is clean and the carburation and timing are spot on.

Look at your engine parts (if you have not yet cleaned them) and you will see part of the head, top of piston and top of barrel have tiny grey fleks on them. On the head these are in a paler / less coked area. These grey fleks look very much lke where the shockwave from detonation has blsted away the carbon. Also I see there is pink build up in the water passages. This occurs where long lfe OAT antifreeze (usually VW / Audi type) is put in an engine that has been run on standard ethylene glycol for some time. If the coolant system is not chemically cleaned and flushed before changing to OAT this insulating layer builds up and causes overheating which can lead to detonation. The cost of mixing antifreezes can be high. A couple of years ago I know of a 125 Beta where the parts came to well over £300 and I have seen cars written off because of it. Although its going to cost you a bit now the upside is if you put in new main bearings and seals whilst you have engine out you should be trouble free for 5 years +

phone 07900 288705 he is in crook / toft hill area

# 41 and 42 - my joke about comparing golf in the desert (just too many bunkers) with trials in Belgium probably takes a certain English type of humour to appreciate it. I actually learnt much of my bike control in a gravel yard lapping it speedway style and bouncing my front wheel off buildings and doing tight turns in allys as well as man made obstacles such as riding along sleepers on edge or over 40 gallon drums. Cheers

Your comment on compression and "hard enough to kick over already". As I said previously there is evidence of what may be detonation which could be caused by too little squish clearance. Get this checked when your engine is rebuilt. Too cool running rarely causes coke in an engine. The usual cause of the dark stains on your piston skirt is blow by and overheating which are made worse by insufficient oil in the fuel. In the last few week I have stripped 3 engines. The 97 (stripped for inspection only) had been run at 30:1 fuel to oil and had virtually no carbon on the piston and the crank case was clean, the second was an 09 (gearbox broken) run at 75:1 and there was a lot of coke on the piston and crank cases. The third was a 2011 50cc 16 year old road legal scooter (piston ring location pin sheared) with separate oil tank and it had significant coke on piston skirt , top of piston and crankcase.

it can't be seized or no one could get t to run at all but a partial seize nipping a piston ring has in the past resulted in odd symptoms that are difficult to diagnose.

None of them are built as well as a Honda CR500 motocrosser of 25 years ago or as reliable as a TY250R of the same era. I recon its down to trying to make them too light, carelessness on the part of the designers and buying in cheap components. For those who can't fix things themselves gas gas gearbox problems are a big turn off and I know of several riders who have shifted to sherco or beta for this reason

You would'nt expect to hold golf tournaments in the desert so why try to hold trials in Belgium?? Seriously though Eddie Lejeaune managed no stop OK

Just to rule the possibility out completely drain and clean the tank, fuel lines and filters and refill with fresh fuel. Other than dirty fuel carburation is unlikely to vary, as are mechanical items so that points to a wire intermittently shorting or going open circuit