woody

There's not much info on it and as far as I know it's not an 'offical' ACU series which is maybe why there is nothing on their website about it, I haven't looked. Tim's idea was to run as a regional pilot this year with 4 or 5 rounds and if interest took off expand to a full series next year if clubs are interested in organising a round It's called the Central England Classic Championship - Cotswold Cup, Sam Cooper, Greensmith and Guy Fawkes. I haven't seen any dates other than the two Midland Centre trials as they're on our calendar, Sam Cooper 26th May and Greensmith 20th October I just hope there is room on the calender for all these events as more and more are appearing and there are going to be clashes Some info here https://www.oldbikemart.co.uk/coming-up-in-the-december-issue-of-obm-central-england-classic-trials/

Common answer is petrol but if you look at the underneath of the tank is that discoloured too? Usually not, my SWM tank was still perfect yellow underneath and also under the tank badges if they were removed, whereas all surfaces touched by sunlight went darker.The entire tank surface should be affected if it's caused by petrol shouldn't it? Ultra violet from sunlight discolours plastic, just look at garden furniture or kids toys like slides, plastic bikes, swings etc. If these tanks seeped petrol vapour like they're said to, if you left one in a closed garage for any length of time it should reek of petrol, so why don't I smell any?

No is the short answer and I've no idea how or why claims like that originate. Not a full 350, only 302cc so no Bultaco 325 type power on tap but noticeably more than the 250 which is fairly flat. It will pull 2nd or 3rd gear better where the 250 struggles. Later TR77 versions supposedly have sharper porting than the white bikes but never tried one so can't comment. Mine is the first model from 1975 and is a nice bike to ride. Just shave a few ounces off the ignition flywheel for quicker pick up if needed

KIA series in the Spanish class - just me and Chris Myers on Bultacos The rest seem to be facebook queens...

I have one of these kits and it worked fine to remove the drive gear on my 247 https://www.machinemart.co.uk/p/cht249-14-pce-bearing-separator-angle-ge/

The shock bolts are normal M6 on the earlier bikes, MK1 2 and 3, they went to M7 on the green bikes Strangely, the fork yoke bolts are M7 on the earlier bikes and changed to M6 on the later bikes... Fitting the engine, I've never been able to fit one with the barrel in place, or remove it. I take the barrel off before removing and fit it after the engine is back in the frame - I could never do a rubik cube either...

Ford silver fox used around 1970 is a good match but not sure where you can get that now unless a local paint shop can mix you an aerosol for it. I don't know the RAL code. NOTE - If you use Halfords paint it will dissolve at the merest touch of petrol, it will need a coating of petrol proof lacquer otherwise you'll be really peed off with the outcome. And whereas Halfords paint does spray very nicely and evenly out of the can and leaves a really nice finish, their petrol proof lacquer doesn't, it splutters out so you need to be very careful when applying it

This is the same casing as Scotty's bike as all the MAR models had the same casing it's just that the one in your picture is in original condition. Many UK bikes had their casings modified with the slot cut in and the back end cut off to relieve mud build up and also to help hook the chain back on using the slot should it have come off the engine sprocket. See the casing in the picture on my bike. The back end of the case can also get smashed off by a chain derail and it's not uncommon for the bottom rear screw mount to be missing altogether. You're right about the mudguard brackets which is a good ID point but it looked as though it is missing in the picture. I was just meaning the basic frame is the same - on all MAR models in fact apart from the top shock mounts on MK3 and green bikes. I think the Verde also has the short swingarm and mudguard bracket I think Scotty's bike is a MK1 with replacement tank and panels rather than a bitsa, in which case the forks and wheels should be MK1 also

It is a MAR. The MAR ran from '71 right through to '79 and changed little. The MK1 ran from '71 - '73. In '74 it became the MK2 MAR with a longer swingarm, bigger crank assembly and the inlet was changed for a push on not bolt on carb. Hubs changed (although externally looking the same apart from black, not polished) to take slightly bigger brake shoes. Green tank stripe changed from broad stripe from side to side to thinner stripe running lengthways. Biggest change came in '76 with the MK3 when it received angled shocks, longer forks and a longer front pipe. In '77 they changed it from silver frame with white tank and sidepanels to black frame with green tank and sidepanels and changed the rear silencer for an abortionate looking thing stuffed with wire wool. On the green bike the barrel got different porting (maybe) and in '79 the frame and mudguards also went green. It was referred to as the MAR throughout this time but I guess in reality the only true MAR was the MKI1 which ran from '71 - '73 as Mick Andrews had leftt for Yamaha by then. You have a MK1 or MK2 frame (they're the same) which would have been silver. If it has a frame number on the headstock which begins 340--- then it's a MK1. If there is no number it's probably still a MK1 as they usually had a sticker with the chassis number rather than it being stamped. The engine looks MK1 due to the split outer fin on the head and the inlet manifold with studs to take a bolt on carb - these could obviously have been changed in 40 odd years but again, the engine number will tell you as it will also begin 340--- if MK1. You need to know for an engine rebuild as the MK1 had a smaller crank than the following models and the crank pin is stepped. The later pin won't fit. The head is on back to front but it doesn't actually make a difference to the way it will run. The tank is from the last green model, it's not the original. The original would have been fibreglass and a different shape. From MK2 onwards the UK bikes had an alloy replacement, different from the original fibregloass shape, which was the same whether for the white and the green bikes, apart from the last all green bike where it had the extended front part like yours. Side panels also look as though they are from the green bike but there's not enough showing in the picture Bike below is a MK1 with a longer MK2 arm and MK2 barrel. The bottom picture is a MK2 but with the original fibreglass tank

Anyone out there who owns, or knows someone who owns an Ossa Pennine trials. Alan Wright is looking for one to display at Telford in February, so if you have one that you're willing to show or know of someone that might be, then Alan would be keen to hear from you

Press in, just two cups and a ball, same as those in your picture apart from no extensions either side of the middle component for O rings. Mine are a few years old now but assuming they still use the same set up. I'm not familiar with the latter set up you mention but I don't think I actually know what a 'proper' spherical bearing actually is... When I showed my local bearing supplier the bearing/bush from my Magical shock (referring to it as spherical) to see if he could supply them he said no and that they weren't spherical bearings

Very similar to the bearings fitted to the Magical shocks, except those fitted to the pair I had didn't have the O rings. Had them fitted for a few years and didn't give any trouble, no wear etc

If they're being fitted to a MAR then the top shock mount is bigger (at 14mm if I remember - it's bigger anyway) than the bottom mount which is the more common 12mm The way I'd do it is to just fit a normal rubber bush with 14mm id to replace the rose joint bearing. Falcon do different size bushes and as B and J Racing Products in the US are Falcon agents, they'd probably provide some

Slight problem in that I can't post new photos stored on my PC - these were old photos I'd put on from years back and are already stored in TC somewhere. You can see the forward/back positioning from the photo above (not saying it's correct but works fine for me) and in terms of height they are just on spindle height. I was told by Mick Andrews years ago not to go any lower than that (at all, not just a MAR). I have two MARs and on one the riser is 10mm (just 10mm thick flat bar under the bottom bar mount) and on the other I don't have a riser as never got around to it. Both have 6" bars Apico do a bar riser kit which I've used on some bikes and it gives between 20 and 40mm increase. The bolts with the kit are no use as they are 8 x 1.25mm 7mm are hard to find but I bought some from ebay, or maybe just found some from the net, can't remember now. Or maybe you could tap them out to 8 x 1mm fine thread as they are easier to find

One of mine - just lower, not back or forward. I don't begin to understand any of that percentage gobbledygook.... sounds like over analysing to me... PS - brackets are braced behind if they don't look strong enough

I'm 6' 3" and had no problem at all with riding position on Ossas, Montesas and Bultacos back in their era for the simple reason they had at least 8" high bars then... So although the footrests were relatively high in comparison to modern bikes, the riding position was ok. The bars now are much lower and I am bent over far too much with standard footrest position - and a lot older... So I lower them - and use bar risers Back in the 70s on a 159 Bulto (pegs are quite low already on Sherpas so you can't lower them by much)

The rim is normal Akront fitted to most bikes in 60s to about 1972 when Bultaco, as well as Montesa and Ossa all swapped to flangeless rims. On Sherpas, that style hub used a flangless rim but it's 40 odd years old and in that time could have been fitted with a replacement rim. A MK5 (maybe MK4 as well) Pursang used a flanged rim with that type of hub. You will have to measure the inside diameter of the hub. As mentioned before 125mm is Sherpa, possibly early Alpina also. Pursang will be 140mm I think from memory. They look the same in appearance. You're going to have to know which for the brake shoes your going to need as you can't use those...

That style hub was fitted to Sherpas in 1972 on the M91/92, but it had a normal rim, that flanged type was last fitted to the previous model 80 with full width hub (on the front) Pursang and Alpina also have that style hub but slightly bigger in diameter (on Pursang at least) Sherpa diameter is 125mm so if it is bigger it is Pursang or maybe Alpinaa

Not sure which needle roller bearings you mean? The MK1 mainshaft runs on normal roller bearings and the layshaft runs in bushes. On later MAR, TR77 on, maybe MK3, the layshaft runs in needle rollers rather than bushes but they won't work with the earlier gearbox as the shafts are different lengths and diameters on early / late boxes, even though they look identical side by side In all gearboxes there is a needle roller under the 1st gear cog on the layshaft - I've never had to change one of these as never seen one worn. There are two that the final drive sleeve gear on the mainshaft runs on. Never had to change these either. None of them have serial numbers that I've ever seen so you'd need to measure and obtain from a bearing stockist if you want to replace if none of the old Ossa dealers in the US stock them. Not aware of anyone in the UK or Europe that does

Yes, as above, there is a thin cover plate that fits over the spoke heads, just prise it off. It's probably stuck on with a bit of corrosion

Once you start tinkering with these babies, you have to hoard.... re: front wheel, the spindle diameter is larger on the older type wheel so to fit the later wheel you'll need the later spindle and need to sleeve the spindle housing in the forks, maybe just on the brake side, but can't remember. Just a thought, if you can find a later type torque arm they have an extension for the outer cable locator which is a bolt on part, as there is no lug on the brake plate on the later wheel, With that, you might be able to reverse the brake arm if that's what you want to do. Not something I've ever done on my own bikes but I understand the point s/s was making

The front end is the same on M27 49 and 80 so it would suit any of those for someone wanting an original set up. Some later bikes also ended up with the tapered forks as well. At least with that front brake you won't have the problem of chrome peeling off

Re: front tbrake set up - the front end is from an early bike like the M80

From what I can see of it, it looks like the hub used on the Sherpas from 1975/6 M159 up to the last 199b model. Off the top of my head I don't know the diameter. I'm not familiar with Alpinas so don't know what hubs they had, but don't think they used hubs like that. There should be a steel ring plate cover that fits over the spoke ends and is held in place by the sprocket