section swept

If you understand ‘sprung’ and ‘unsprung’ weight then setting up the sag is one part of getting the suspension adjusted to suit your bodyweight. There is the weight of the bike plus your weight to carry about on two wheels. Hence some of the top riders have invested time and money to arrive at the best compromise to allow the front and rear wheels to follow the ground without boing the bike all over the place. You can adjust the front forks with different strength springs and spacers to make the springs react. Rear suspension can be set again with different length shocks, less or more powerful springs. Then there comes the damping which controls rebound and with further mods to sone extent compression. So if you get on your bike and the weight of yourself compresses the suspension too much then your ride is going to be seriously compromised. Bike sag = the suspension supports the bikes sprung weight normally about 10-15mm ( bike lifted up so weight is off suspension then allowed to settle perfectly upright...measured at a fixed point) Bike sag with rider (in riding kit +helmet and gloves) Rider gets on bike with bike in upright position total sag now measured. Should be approx static sag + second sag approx 25-30mm Applies to both ends ? All pivots and levels accepted as in good order. NB Some riders have carried out suspension set up with the tyres removed from the rims to get exact movement...extreme but valid.

Don’t look down at the front of the bike, look straight ahead at some readily available fixed point. Now when your balance starts to wobble it should be easier to compensate with body movements or slight bar or footrest pressure. Thats the best bit of advice to practice varying foot pressure from side to side. Tyre pressures will have a marked change, with low pressure there is more tyre surface to act upon. But then again some might say the softer tyre walls affect the balance more. I now have Labrynthitis so my balance is questionable. What I do is to ride my mountain bike around slowly in as tight a circle as I can manage to try to re-train my brain ( yes I have one confirmed by CT scan). Static balancing on a push bike is also good for the morale!?

Rock the bike and get it into neutral. Make sure it is neutral and not a false position. Start the bike and get it thoroughly warmed up. Make sure you have approx 2-3mm free play at the clutch lever ( on handle bars). While you are warming up the engine operate the clutch lever a few times. Now kill the engine, select second gear and try to move the bike with the clutch lever pulled in. If its still stuck then the first course of action is to dump the clutch oil and fill with the correct quantity of ATF. Now each time before you start the bike do as previously suggested, select second or third and pull the clutch in and rock the bike back and forth....this normally works. Even if you stripped the clutch and deburred the clutch basket and thoroughly checked the plates you might still have a stuck clutch after a few days standing idle. Bultacos suffer the same issue....not all but quite a few. Making sure the clutch operating mechanism is well serviced and set up is a good idea in any case, especially ensuring the best cable run and cable freedom. Hope you adjust to the issue??

Just thought I’d show you my version of a chain guard for the Montesa 348. Didn’t like the idea of paying upwards of £50 ish for something that might get wiped out in a section. There is a chain tensioner courtesy of In Motion nestling next to the gearbox sprocket, the upper chain run is protected by black water pipe ( cheap to replace if it breaks) the lower chain run is protected by thin pond liner sheet, this deflects falling crap from the tyre. There is also a lower chain guide made from bullet proof nylon (well the guy who gave me the plastic said it was ballistic grade). Hope you like. Any exposed glue (Gorilla) has now been carefully removed...it was just a belt and braces finishing touch. You will probably notice I have used the original Montesa chain guard swinging plate

You may want to think about using a taller gearing set up as trolling about on the Isle will stress your bike especially the engine, tyres will wear rapidly to. Old engineering proverb.....the faster the speed the faster the wear rate. Thats of course if you intend to use the main roads.

Sorry for the late response. No mods to clearance, although the suspension is close it does have clearance...about 1/8th of an inch. The drop bracket is a piece from a Scotoiler Kit?. The connection from mid to tailbox is unmodified save for a new rubber O ring seal.?

It wasn’t only a Bantam that got the exhaust/frame treatment there was I think a Metisse with a Triumph engine where the exhaust down pipes entered into the frame lower tubes and exited just before the swinging arm. In both cases I think there would have been heat issues and especially with the Bantam. Imagine the load and stresses being put through the exhaust port, securing ring and frame connection.

Bit like being told a juicy story and then the teller buggers off leaving you deflated.

Heres my M80 with later rear box

Best thing to do first is slacken all the engine mounts and the swing arm pivot, thats slacken not totally undo. Now pull and push the engine to see if that crack can be closed up. Do not try to weld before doing this as it will probably snap again. If the gap can be closed up then a good TIG welder might, I emphasise, might be able to weld it up. Being based in Sheffield you should be able to find a competent person. You will need to remove the engine so that the welder can get best access to all of the crack in front and behind for both cleaning and weld preparation. Has the bike been dropped on its side? Has it been yanked down too tight when transported? You may consider some form of extra support brace from the cylinder head bolts.

Gearbox oil....check or replace...read replace with correct grade/ viscosity. Otherwise like other members have stated....sounds ok. Try clutch in and in gear that may take some noise away. Listen to other trials two strokes some make a hell of a racket yet are perfectly ok.

A days work, take out fag breaks, loo breaks, meal breaks and mobile phone checking.....actual work time 4 hours assuming nothing is seized or broken and no mods needed to make parts fit new frame. I see feetupfun reckons on 2 hours, in reality he could be right but time and motion means there is no time to search for tools and move about to clean and inspect items. Choosing my words carefully the professional/ experienced individual would want to ensure that no damage is done by hasty dismantling and transfer of parts to the new frame. Half an hour just to sort the head bearings unless new ones are going in then 15 minutes. That leaves an hour and three quarters to do the rest....

Clubfoot (rear box assembly) will need to be cut open and repacked, caustic soda will not clear the packing very well. Not sure but one specific type of Bultaco rear box is quite restrictive and reduces power. Check out more info on the Bultaco site of Trials Central.

But Greeves aluminium frames are getting quite old so may be suffering from degradation/brittleness in the mounting areas. They look dam strong and no doubt are but need careful checking, just like alloy wheels on both bikes and cars. Same thing happens to scooter frames as to your bike (just for interest) the older they are the more likely they are to snap.

Erm Denim Jeans...for those of a certain age, black denim is better than blue. Any of the good work trousers advertised by the Diy stores...some have more benefits than actual Licra tights that are ‘for trials’. With Belstaf and Barbour you run into weight issues, especially if you wear the jackets as well....but thats what most used then in the past.

You don’t say if you are using the cast iron cylinder or one of aluminium alternatives. Lengthening the inlet manifold by (as much as space allows) I used to fit an inlet manifold extension 2inches long which produced more low down torque or plonk. This tends to reduce the engines high rev performance. Fitting more than one cylinder base gasket has the effect of altering all the port and transfer port timing and can be a useful way to experiment without machining the ports. Compression ratio is reduced by a tiny amount, but skimming the cylinder barrel top restores it. I used to cut a window in the piston to allow the inlet longer exposure, this requires careful measuring and careful checking with the inlet manifold off to allow the piston skirt at tdc to be marked. You do all of this at your own risk. However most Villiers engine officionardos will probably say to leave well alone and concentrate on getting the carburation and exhaust spot on. Crankcase stuffers can improve the crankcase compression, as can ensuring the main bearings and seals are in perfect condition. I would add that most people using the Villiers engine just use them as the factory built them, including the then of the time works riders. Most preferred the bob weight original crankshaft, in my last Villiers 32A I fitted a full circle Alpha-Stepha polished crank assembly with knife edged connecting rod. That all sounds good but in reality there isn’t much difference between the two. Good fuel, the correct oil and mix ratio, clean carburation, optimum ignition setting and making sure the drive side main bearing receives adequate cooling ( the crankcase design shrouded the housing too much) and a good 32A motor should see you happy.

Does anyone speculate as much and pore (lust) over a page three model like they do the supposed latest trials bike??????

Dont just measure and transfer one bikes peg position to another. Work out how the rear brake will need to be modified if at all. Gear lever will this be ok for you further away, most probably. But.....sit on your bike with some blocks of wood on the floor level with the rear wheel spindle, arrange the blocks so that you can stand up and judge where best to position the pegs. This could be 3-4 inches back and down from the original by perhaps 2 inches or more to be level with the rear wheel spindle. Any lower and you will be banging into obstacles with the feet and footrests first before the wheel can raise you up. Experiment in this way until you are satisfied that you have a good position. Measure twice weld once??

Automatic transmissions run ball races, needle rollers and bushes and thrust bearings that all take a hell of bigger load than any bike engine will ever know. HGV Auto trans run with ATF...now there is a load....then theres the 4X4 SUV’s etc that most run auto trans. Straight 0w oil is for cold start up to ensure lube gets to the high areas but then when the oil gets to operating temperature it needs the next level of a multi-grade eg 0w 40 etc otherwise the oil will start to fail. Main bearings in 2T engines are nearly all lubed by the oil in the petrol mix. There are exceptions, Honda with their Enduro styled CRM used oilways from the gearbox to the main crankshaft bearings which needed seals on both sides of the bearings for obvious reasons, the disadvantages are that when the crankshaft bearing oils seals wear the oil from the box is drawn into the combustion process. This has the effect of lowering the octane rating of the fuel, smokey exhausts and rapidly diminishing gearbox oil! Additionally any metal particles from the gearbox might end up in the main bearing or restricting the oil way. This process used no pump so it was just gravity and the oil throw from the rotating gearbox components, so on very long uphill steep climbs the main bearings were left pretty much to their own devices i.e. marginal if any lube? Some vehicle gearboxes employ oil pumps to ensure adequate lubing, others use a type of guttering to catch the oil and direct it to (mostly) gears that by design were too high up to receive oil splash lubrication. All modern lubricating oils commercially available will contain detergents, part of the oils job is to lift and contain any contaminants and particles and then carry them to a filter element, guaze or pass over a magnetic trap/pickup for collection to keep the engine...gearbox free of damaging stuff. Thats a good reason why some riders change the gearbox oil very frequently possibly after each ride/event. Take your pick?but the petro-chemists know best backed by research and testing.

Maybe change the fork oil and check that the fork springs have not sagged too much.?

Automatic transmission FLUID is designed to flow through the valve chest to operate the selection of brake band servos ( to engage or release a planetary gear set) and system control valves such as the ‘ kick down’ system ( theres more but thats enough for now). This Fluid has to operate straight from cold and all the way up to high temperatures 100+degrees C ( hence the transmission fluid cooler)due to the fluid having to flow through the torque convertor ( stator, turbine, impeller etc) to create drive from the engine to the transmission until ‘lock up’ when you have 1 to 1 all components in the torque convertor rotating at the same speed. Mercedes Benz used ATF in some of their manual gearboxes to enable easier gear shifting for the driver at the cost of added gear noise at idle when you could notice it. Many other vehicle manufacturers use ATF in their manual gearboxes but now there are specialist oils specifically developed for a particular gearbox. The straight cut gears in a motorcycle gearbox will happily churn away in what ever oil you care to treat them to, too thick ie EP 90 in some cases can cause stiff selection and that grade is not necessarily suitable for some clutches if lubed by the same gearbox/sump. Straight cut gears will put up with a tremendous amount of load and poor gear selection by the rider, unlike the helical cut gears in a car gear box. Indeed the main reason that you can select a gear without clutch use when moving is the dog teeth desin In so far as using a multi-grade engine oil in an agricultural machine with a form of automatic transmission I would not like to pass comment. But British Leyland used multi-grade engine oil in their automatic transmissions, the Maxi, the 1800 and 2.2 Land Crab, the Mini, 1100 and the Allegro all disastrous vehicles as automatics. They had to use engine oil because the gearbox was also the engines sump! Can’t remember any that operated smoothly or did not require major transmission work at some stage in less than 30-40,000 miles. The oil needed changing every 3,000 miles because it got so trashed trying to work as an engine lube and an auto transmission fluid (which it wasn’t)! Mainly the clutch packs burned out due to the oil breaking down due to the high temperature the oil was expected to work at! Some auto trans fluids can contain certain chemical additives that will attack and destroy bushes used in some transmissions so check before you bung any old fluid in. ATF lends itself to motorcycle all metal clutches and drive pinions or chains because it can deal with the sudden rise in temperature generated when the clutch is slipped etc. Again as the ATF is chemically designed to operate with friction materials (clutch packs and brake band linings) it can be ideal for those bike clutches that employ friction blocks, corks, glued on friction material etc...not for all but most??

Oh yes very EU over there....all makes us over here in UK sticking to the rules the underdog...again!

Keeping to the original hubs would be a good thing, then later when you know more about pre 65 and acceptable mods you could make those changes. Cost may mean you keep the bike as is?

Hope you are right with that choice?

Someone in the the Beta design team has produced a nice little profit earner with brittle mudguards.