woody

Looks like most of your questions have been answered but what do you really want to know in the context of are they alright? It's subjective and personal opinion. Yes they're a decent bike but not as good as the Bultaco of the same era as they had virtually no development from the original MAR, just longer travel suspension with angled rear and longer forks, revised porting on the cylinder which made them a bit quicker on pick up as the MAR has a fairly docile power delivery. Longer front pipe and one of the most ridiculous rear silencers ever stuck on a trials bike. Green bikes usually had points, Ossa went back to electronic on the Grippers. The green bike with the black frame was 1977, hence TR77, the green frame was introduced in 79, TR77 Verde and was the same bike apart from gold rims and all green frame and guards. The 350, usually called 310 is actually 302cc. I've never ridden a 350 TR77 so no idea what they go like and never ridden a 250 TR77 in sections, so can't really compare with the power delivery of the earlier bikes. I've got a TR77 350 cylinder and it is slightly different porting from my MK2 350 cylinder but how that translates to performance I've no idea. I had a MK3 MAR years ago for a short while and it felt too high with the long travel suspension and needed the forks pulled up through the yokes to make it steer like the MK2 which is a very good handling bike. Maybe it could have done with slightly shorter rear shocks too but Ossa actually moved the shock top mount on the TR77 which probably had the same affect. It's all academic now as when the bikes were new, top centre and national riders would have needed the bike to be as competitive as possible against the bikes from other manufacturers. Nowadays, the sections ridden in classic trials are nowhere near as hard as sections from centre and national trials back then and the bike, even in standard chopper form, is more than capable of handling classic events. If your not riding it in trials it matters even less. Maintenance is no different from other bikes. Yes it has the same oil for clutch and gearbox, 800 - 900cc, but can't see why that is an issue, the Bultaco and Montesa are the only bikes I can think of off the top of my head that have seperate gear and clutch oil. Points maintenance is no different from other bikes but if it has electronic it needs none, just check inside the casing now and again to make sure there is no water in there as the timing cover isn't a brilliant fit in front of the drive sprocket. A useful mod is to move the wires from the stator from exiting through the bottom of the case to exit through the front of the case. There are articles on here somewhere describing how to do this, if not already done. When the wires exit from the bottom they are bent 90 degrees and can get trapped between the sumpguard and engine if the sump has had a good battering which can split the insulation enough to short out the wire and kill the spark. Same can also happen if the insulation has gone hard / brittle over the years.and cracked. The rear brake plate has a flange / slot in it to locate on a lug on the swingarm instead of a torque arm. The alloy of the brake plate is very brittle and if there is any chatter in the fit of the slot on the lug it is possible to break the top flange of the slot clean off if the rear brake is applied hard, meaning you have no rear brake as the plate is no longer fixed in place and free to rotate (I've done it on 3 bikes over the years) It's probably beneficial to pack shims to remove any slack if it's possible to do so and eliminate any chatter from the brake plate. Lastly, all UK bikes had alloy tanks so if the one you're looking at has fibreglass it's probably a later import, unless someone has retro fitted a glass tank. The black framed TR77 had the same alloy tank as the earlier bikes but the green framed bike had a re-shaped tank with an extended front

Yes, it happens, dirt and gunk can get down the pushrod tube and can cause it to stick. I've had it happen, not enough to stop the clutch being disengaged but enough to overcome the springs and prevent the clutch from re-engaging when the lever is let out.

On a 191, only a 325 exhaust will fit (from model 159 onward) The early 325 motors, up to 151, were essentially overbored 250 motors and used the same diameter pipe and bolt on stub as the later 250 (from the model 158 onward) As Larry mentioned, 250 up to model 150 used the threaded collar. The new design 325 motors from model 159 onward, used a larger diameter manifold and stub than the 250 and even as a complete unit they aren't interchangeable because the 325 stud spacing also is wider than the 250. On the 325, you also need to look out for different diameter joints from middle silencer to backbox when using items from other models as they vary. Easily sorted though by welding on new pipe to make the required size coupler

For a UK MK2 MAR the tanks were made and painted here and the decals were made here so they were never the original factory colours, whatever they were. I always used Ford Diamond White. The Goneli rear guard works if it mounted far enough back otherwise they fall short and look ridiculous leaving half the rear tyre exposed, but when mounted like this they only reach under the seat and need another to act as a lower splashguard. The Stilmoto full length look better and the edges can be rounded off at the back if you don't like the squared off look

Not sure if you're on facebook Matt but I've put pictures on. The V behind the filler cap is about right from what I remember but it may be that the point should be a bit closer to the filler cap, but not by much if so. The silver was Ford platinum silver https://www.facebook.com/photo.php?fbid=827035540775641&set=pcb.827036407442221&type=3&theater If you're not able to see them,PM me your email and I'll email them to you

I think I still have a topside picture of the bike I rebuilt a few years ago but won't be home until late this evening, so can't look until then. The original blue was usually similar to the later 340 blue which is RAL 5015 (close enough) I'm not sure where the tanks were actually painted or whether they were all the same colour. Don't know whether Homerlite painted them or left it up to the importer. The blue on the Haynes manual is the more common type but I've seen them darker as well. A mate had one that was nearly new at the time and that was a much darker blue. Impossible to know really whether they were all painted the same and some changed by owners or whether they were different shades from new. I did mine a shade of blue I liked as I'm not that bothered about originality but the pattern of the blue / silver was done to original. I can't post photo on here, I can put it on my facebook page which is open and you can find under Dave Wood - but won't be until tonight

No, when Pedrosa made up ground at the end and looked faster he took Marquez but then went wide which allowed Marquez back through - where people got the notion that Marquez bit straight back and took Pedrosa at will (as evidence he wasn't trying to pass Lorenzo) I don't know. Pedrosa clearly went wide on the brakes. Had he not we'll never know if Marquez could have passed him back. As for Marquez helping Lorenzo by not attempting a pass, there were also a few other races during the season where Marquez followed behind Lorenzo unable to make a pass on him the entire race, both for first or second place - those races are conveniently forgotten when people say Marquez always makes a pass.

They are a 250 engine yes, so converting it to a 250 is easy enough. They have a different chassis from the blue 350 model as they use a chassis from the '76 - '78 250 models, these differed by being shorter and with a slightly different headstock design which used shorter forks and a shallower bottom yoke. This chassis is a nimbler chassis than the 350 and the 250 Sherpas are good bikes, usually overlooked by punters in favour of the bigger model. The 250 isn't lacking in power and a much better bet than 175cc.

In the UK - unlikely, I've never heard of anyone having one in stock If you're able you can make something that will do the job http://www.trialscentral.com/forums/topic/18875-ossa-mar-flywheel-puller/?hl=ossa+cushdrive Where it mentions the plate with the hole in (preferably round in shape) it is also a benefit to machine a recess into the area around the hole so that when the plate is pulled forward to locate against the two collars, the collars fit snugly into the recess which helps prevent them from being pulled out of the groove when you start to apply pressure with the puller

Yes Sam's own development 325 before they went into production, which he probably used to prove most of his own aftermarket parts... He also used a Mikuni on it.

If it's just the 199b you mean, there was only one version but there are minor differences in some components, probably due to what was available at the time they were assembled. Some had an alloy head steady. Some have a bracket on the front down tube in front of the head, probably for a horn, some Puma and similar bikes use that to add a front head steady. Some R/H fork legs aren't drilled for spindle pinch bolts. Some had Femsa ignition, some had Motoplat.

My opinion only, but on an SWM there is no need to even start - those I've ridden are fine as they are and will steer around anything Altering steering on older bikes doesn't always give a benefit. I've a 340 Sherpa with altered steering and I'm not convinced. I'd guess there is a fine line between making something marginally better and ruining it

So when is someone going to discover EOR 2K

I've always liked the Spanish bikes but as to which is better, the SWM from yellow/black model is the better bike. Only thing that lets it down is the clutch but it can be sorted. Once you get to the Jumbo framed bikes, both 240 and 350, they left the Bultaco behind, as you'd expect. The Jumbo frame 240 is probably right at the top of the twinshock tree, the 350 has fantastic torque but needs someone who can make use of it, a novice bike it isn't...

Gear ratios are fine on the 5 speed, you're never ever going to use 4th for a section but it pulls no problem on tracks, it's not a big enough jump to make the motor bog when going from 3rd to 4th up hills. If you want a real jump in gear ratios, try going from 4th to 5th uphill on an Ossa...

Really, I can't see the point of initially allowing riders to spend money on a foreign carb and spend time getting their bikes set up to run well with it, then revoking the rule so that they have to spend another £150 on another new carb and spend more time trying to get the bike to run exactly as it did before. Just causes unnecessary time and expense for riders It's ok to have a Cub that looks nothing like period and bears absolutely no resemblance whatsoever to a 1964 machine in terms of appearance in either overall silhouette or individual components - which is contrary to the overall desire of maintaining period appearance - but you can't have a foreign carb because it doesn't look period. What is the point really after all this time using foreign carbs? Bring them into line with the Scottish? Why? If clubs want to run events for bikes using only genuine Pre65 parts and of Pre65 appearance why don't they just do that and put everything else in the specials class

Original price he wanted was £4k so yes, £3k over priced at that time. It's been gradually reduced throughout four attempts to sell. £2500 is still way over what it's worth. Ossas just don't make that sort of money. As a bike to use, it needs tyres and shocks which is £300 added to whatever the asking price. Add to that the fact that the mechanical state of the motor is unknown as the statement about a professional rebuild is worthless until the engine is tried and proven to be (I've heard some professional rebuilds before...) so there is the potential for more cost there. You have to wonder how well it would perform with that carb in actual competition as well. A tidy MAR ready to go can be bought for £1200 - £1500 so why would you want to pay £2500 for that one? Half a dozen trials and the look has been scuffed off and lost anyway, along with any 'value' those looks may have added. If it's just for the looks and not to ride, then they're wrong if you want to nit-pick it. Decals are MK2 and wrong shape and colour and the MK1, which is what that is, didn't have the alloy tank and decals, it had the fibreglass tank with broad green stripe painted on, as did the sidepanels. It doesn't even have the Mick Andrews decal... I'd guess the lug on the front fork that holds the brake plate is broken off as it has a heath robinson torque arm fitted which is not a MAR fitment. Guards should be alloy and hubs polished not black. All academic I know but if you're asking top money for a bike, it's only going to appeal to collectors, not someone who wants one to compete on, and a collector, if they know what they're about would expect it to be accurately restored. That isn't. If it didn't have the May connection, I'd wager people would be calling it over priced. To have one just to look at, you could buy a bike for around £700 and just do a cosmetic rebuild on it, not having to worry about mechanicals. It would look just as good or better than that and you'd still have change from £1500 total. Seller is just trying to make a killing using May's name

It's about the fourth time they've tried to sell it now. I've no idea why a bike sitting in James May's shed for 12 months adds about £3k to the price. No-one in their right mind would pay that for it. I read 'thinning my collection' as I bought this hoping to make a quick killing with it

They're made here http://www.tyoffroad.co.uk/

46 rear was standard on the MK1 MAR with, I think, 12 front, They went to 11 / 42 with the MK2. I've run 10 / 42 a few times over the years mainly for a low 1st for real nadgery stuff. To fit a 10 tooth you need to space the nut away from the sprocket as the chain can catch. There used to be a nut with a shoulder on one side to space it away from the sprocket but not sure if you can get them now.

Is it just the light from the other end, looks odd as the bearing spacer is tilted? MAR doesn't have those raised bits in the castings for the nut retainers and bearing housing looks different (from the photo at least)

I've had a 10 tooth but there are no manufacturer's markings so no idea who made it, but Talon don't do them off the shelf. They will make them to special order, and it's about £90 for the set up. With a 9 tooth the chain would probably foul the sprocket nut. In Motion here in the UK will have up to 48 tooth I think for a 528 chain - edit - I meant 520

That cost is to make the modification when they're first being built new, not to modify an existing pair, that will cost a lot more as it will be a strip and rebuild which will involve new seals, bushes etc as Robin won't re-assemble with the old components. They are also old Falcons looking at the design, colour etc so not sure they could be converted. I couldn't see your picture originally but can see it now - as someone else pointed out the rod should go on the inside. It should still bend around the inside of the shock ok. It's the same issue on all bikes now since all shocks became upside down

As someone else mentioned, it sounds very much like a blocked pilot jet or maybe the pilot circuit itself seeing as the bike has been standing for a few years. The pilot circuit can stop a bike running altogether if it is blocked. Crank seals wouldn't give the problem you have. Carb cleaner may not always penetrate a blockage, a sonic cleaner as you've mentioned should have more success. Also, a friend of mine has had success by gently warming a carb with a blow torch (obviously you need to be careful with how much heat) which has melted some sort of gooey deposit in the pilot circuit which his sonic cleaner didn't remove The Amal carb itself is fine unless it is worn (same as any carb) If it isn't blocked and it's not worn, with new jets and slide etc the bike will run fine. I'm using a MK2 Amal on a 1972 325 at the moment with no problems.

No you can't, they are made to work with the body at the top, they won't damp properly if you fit them with the body at the bottom. You should be able to bend the rod to clear the spring as it's the same issue on most bikes