woody

It's difficult to give an impression of the TR77 against the original MAR as my experience of the later bike is virtually nil. Just a brief go on a standard bike recently, as mentioned above and a go on Martin Beech's reed valve TR77 many years ago, but neither on proper sections. Many years ago, I had two consecutive MARs, both '74 bikes. I really liked them and the second one was probably the bike I gelled best with out of all the bikes I've ever had. It had to go as I'd started work and needed another car. I bought another bike as soon as I could but it was a M159 Sherpa 325, not another Ossa. Not long after, my brother got a MK3 Mar. At one trial the Sherpa wouldn't run right so I took the MAR and used that, first and only time I've ever ridden one. My impression was that it was a tall bike compared to my earlier ones and that it didn't feel quite as stable. It was as standard, so the forks weren't pushed through the yokes, it was still like a chopper. I thought they'd spoiled the bike at the time. On all the bikes, MK1 through to the Verde, the frame is exactly the same on each. The only difference is swingarm length, fork length and shock position. The MK3 on had more ground clearance than the previous bikes thanks to the longer forks (2" at least) and the repositioned shocks lift the back end slightly by pushing the swingarm downwards to the rear. But they seem too tall at the front with the ground clearance lessening towards the rear. If you an find a picture of one side on, you'll see what I mean. Dropping the forks through the yokes on later bikes, to give the same length from spindle to top yoke as the earlier bikes, should in reality give the same feel as the MK2 as the difference in height at the rear is minimal and could be lost with spring preload, It is that minimal however, it's probably not worth it. I think, with the MK3 / Verde set up this way, if you rode one alongside a MK1 and MK2 and didn't know which you were on, I think you'd be hard pushed to tell which one you were actually riding. The gearbox changes were needle rollers on the layshaft instead of bronze bushes from the TR77, and at some point, maybe the TR77 again, the addition of two pins to the underside of the selector shaft fork. The only reason I can think of for the addition of the two pins was to keep the gap between the fork tips and the selector drum within the recommended measurement

There's nothing in the rules as far as I'm aware that prevents this but the practicalities of sharing make it difficult. By the time one has ridden the section, gone back and handed the bike over, there is a fair delay before the second rider completes the section. Especially if it is difficult to get the bike back to the start of the section, depending on section location etc. Multiply this 40 times for a 10 section 4 lap trial and you could still be on your second lap when all other riders are finishing. Then you have to consider observers, who aren't going to hang about for a prolonged period for two riders as they'll think you've retired when you don't appear on consecutive laps like everyone else. You could put your faith in the goodwill of other riders, queue together which means that when rider 1 rides the section, rider 2 stays at the head of the queue and rides immediately the bike is returned. If other riders are willing to let you get straight on it and ride, it would at least get you through the sections quicker. I guess some will be accommodating, some will whinge.

Just the trials, there's no practise at the venue

Yes, given the conditions, that's the best option. Been up today to set sections. Very very wet. The weather forecast for the venue, on the BBC website which I checked before I set off this morning, said fine weather from tomorrow through to 27th, so sections will dry out to some extent and have been set with that in mind. Then I get home and see an all new forecast with torrential rain forecast nationwide tomorrow and carrying over onto Tuesday... Great, the weather shafts us every time we have a trial. Never mind, it'll be ok on the day, I'll be up there at first light on boxing day to make any adjustments

Hi Hamish - be a nice bike for that class. There are 3 versions though. MK1 250 up to early '74. MK2 from mid '74 up to late '76 which included the 310 from late '75. MK3 from late '76 up to mid '77 which was the MK2 with longer front forks and angled rear shocks,. At some point it also got the longer front pipe, but that could be classed as a '77 version. Not much to look out for that differs from any other bike really. If looked after the motors are very reliable. Gear selection can sometimes be not as positive as others, say a Sherpa, but that can be caused by the gearbox not being shimmed correctly when reassembled. Having said that, shimming is a nightmare and trial and error and I've had them working perfectly, only to find no shims at all when the engine has been stripped for a crank rebuild They're a nice handling bike, pretty neutral but with quicker steering than a Sherpa or Cota. The MK1 up to early '74 has a shorter swingarm so it is very nimble in tight stuff and changes direction quickly up rock streams. The MK2 had the swingarm lengthened by 1.25" to make it a bit more stable up climbs and grip better but you'd b hard pushed to tell the difference if you didn't know. The MK2 also has a bigger crank assembly, therefore the MK1 should pick up revs a bit quicker due to less weight to get moving. The MK3 felt too tall with the longer forks and angled shocks and most riders dropped the yokes and had about one to two inches sticking out from the top yoke. The shocks were maybe a bit too angled though. On the green bikes they raised the top shock mount a bit but they are '77 bikes. The 250 engine has a lazy power delivery, being quite soft in comparison to say a 250 Sherpa. They rev like hell so 1st gear covers a lot of options in sections. The head gasket is actually an alloy spacer and comes in several thicknesses, so compression can be altered by that means. The thinnest is 0.5mm. Standard they generally came with a 3mm spacer, which is what most probably still have. The thinner versions were probably for the motocross bikes. The later green bikes had different porting I think and having tried a standard one for the first time ever a couple of months ago, it definitely picked up quicker than my MK1. Front forks are on the softer side but work very well with a nice action, far better in my opinion than Montesa or Bultaco or anything else from the mid 70s. Back end works well with good shocks fitted. Even with good shocks, the older Sherpas can feel dead at the back but you get plenty of feel from the MAR. Brakes are as good/bad as anything else from that era Motoplat electronic ignition was standard on bikes up to the green versions when they also used points, going back to electronic on the Grippers. It can fail but Bradford Ignitions can repair the stator. The combined coil/CDI unit is still available new. The clutch lever requires a pair of stilsons to operate and if you're lucky may finally disengage by the time you reach the next section.... I've fitted Barnett friction plates to mine which have a greater friction properties than 'cork' plates, therefore require less spring pressure. They also break immediately with no drag. With these fitted and the clutch arm lengthened, the clutch is quite useable. The springs can also be adjusted with the clutch cover still on as you can get at them through the inspection cover - unlike the bloody Sherpa...The nature of the engine though means that you rarely have to use the clutch in sections. The bike can come to a virtual standstill without stalling with the clutch still engaged. I also have a '75 310 MAR and that is a better engine than the 250 (personal preference obviously) It pulls stronger from the bottom and can easily use 3rd in sections if I need. I prefer it to the 250. In terms of mods, the chassis doesn't really need any, other than maybe lowering the footrests to compensate for modern bars which are lower than the bars fitted in the era. I've fitted my own silencer to replace the standard one which can get a bit noisy (it has no packing, just two baffle plates) Carb was an Amal 27mm as standard but they were unique to the Ossa on the MK2 / 3 versions as they were a stub push fitting, not bolt on like the MK1. You can't buy them new but Mikunis were a period conversion anyway. Only mod for the engine is a reed valve which wasn't a factory option but was done by Ossa UK in 75/76. Certainly gives the 250 more torque and pull in higher gears. 310 doesn't need it. If you want to get really clever, 310 reed valve engine with a 250 crank gives a 280cc motor. The reasoning behind this was that the 310 had better power but was a harsher engine, whereas the 250 revved higher and was smoother. The 310 with the 250 crank (shorter stroke) gave more power but retained the smoother 250 characteristics and higher revs. This needs a bit of work to the cylinder to get the port timing back though, spacer under the barrel and about 4mm taken off the top of the barrel. My own experience is that my 310 revs just as mentally as the 250 and isn't any less smooth, which is why I prefer it. That and the red / green stripes... In my opinion, all you need for the Pre77 class is to get the bike working with decent brakes, suspension working well, engine to run as it should with clean carburation, Barnett clutch and lighter clutch action and that's it. 310 would be my preference but 250 is still perfectly capable - plus, the 310 is quite rare from that period. Footrests lowered is personal preference.

I've used Shell V-power (optimax before that) for years and have had no issues with fibreglass or rubber being eaten away. I don't drain the tanks, the fuel is left in.

Yes, I've used them as well as others I know They do a very good job, therefore get a lot of work so they're always busy. Turnaround is usually a few weeks, plus you're right in the xmas period as well.

You just need someone with a lathe to do the shoes for you. Just fit the linings to the brake plate, put it in the chuck and turn the linings down until they fit into the hub. I think the front hub may be slightly bigger in your bike than the MAR, the rear definitely is as the MAR had the same hub size front/rear

Be good to see you there if you can make it. We have a website but it's not that well maintained really as you'll note from the next event info, it's just updated with results from each event, although they are also e-mailed out as well as posted on the front page on here. We're only a small club with 4 or 5 active members involved in putting the events on, so there's not really much info to put on the website. We run 5 or 6 events a year which are advertised on the front page on here as well as the calendar. If it's your 1st / 2nd trial, I'd recommend the easy route as primarily you're aiming for an enjoyable day out. The medium route isn't difficult but the difference being you're more likely to run up a high score on that route which can be demoralising. Gaining experience is all all about learning to read the lines through the sections and getting the bike in the right position to negotiate whatever hazards you face in the section, knowing when to apply throttle, when to back off, weighting yourself on the bike for grip etc. All best done on the easy route to begin with. A few trials on the easy route to learn those basics and you'll soon be up onto the medium. The trial doesn't start until 11, so if you're unsure as to which route to choose, if you get there early you can have a ride down to the sections (about 200 yards from where you park) and have a look to see what they're like before you sign on. Even though it's your first events, if you've practised a lot and become competent in the basics, you may feel you can go for the medium. But riding within the confines of section markers is quite different from practise. Without knowing what you ride like I can only suggest the easy route to begin with. http://www.staffordautoclub.co.uk/

Find somewhere that can reline your shoes with decent material. I don't know what shoes you have available over in the US but the over then counter shoes here are pretty poor. I use a local lining company that have material that gives good results in oily conditions or under water (not sure what the original application is that uses this material but it's nothing to do with trials bikes...) It's not perfect but it's much better than the shoes available from retail. We have them extra thick and then machine them down to fit. The front brake in my two MARs is reasonably good and comparable to most other drum brakes on trials bikes. Of course, if your hub is worn or oval, there's not much you can do with shoes without skimming or relining it.

That's our trial, Stafford Auto, on boxing day. The 'over whatever' reference is just a tongue in cheek reference to the O/40 class that in recent times has evolved into O/40, O/50 and O/60 classes at some events. It will actually be O/40 on the entry form. All it means is however far past 40 you are, there is still a route suitable for you to ride. Essentially, what you're interested in foremost, is which route is suitable for you and it's your riding ability that should determine that. When you've decided which route to ride, then you can decide which class you want to enter and that will depend on any number of factors - your age or the type of bike you ride being the more common examples. If you're over 40 years old and on a modern bike you'd choose O/40 class and probably ride either the easy, medium or 50/50 route. However, you could still enter the O/40 class and ride the hard route if you're O/40 and an expert standard rider. Or you could just enter as expert regardless of your age. If you're over 40 and riding a Pre65 or twinshock bike you could enter either the respective class for the bike or as O/40. It's up to you. You'll find riders of the same class riding different routes. We'll have twinshock riders for example on the easy, medium and 50/50 routes - the hard route too if they're good enough and confident enough. All it means is, when the results come out you can compare yourself to riders on the same route in the same class or with the same type of machine, as the results are categorised by route and then the different classes that rode that route. It's just a club trial, not a championship so you're not bound to one route depending on what class you ride. Whatever your age or the bike you ride, you'll find a route suitable. I haven't been to the farm yet, so not sure how dry or wet it is there, going to mark out tomorrow. The forecast for the venue looks favourable over the run up to boxing day, so fingers crossed.

That last 349 - aka 349/4, 350 or MH349 - is a much better bike than the previous white one. Quicker steering and handles really well. Motor is one of the best of the twinshocks I had a Cota 350 and the only thing that let it down was the clutch action. Rest of the bike was spot on.

Try Steve Goode as he did have some Italjet stuff

Yes, they all use 30204

Yes, easy route will be fine for first time Revs Suspension in Halesowen for the seals, can't think of anyone closer but there must be motox dealers around Bromsgrove who could do them? http://www.revsracing.co.uk/

The TR77 with the black frame had a full length mudguard in that funny off-white material. The later TR77 Verde with the green mudguards also had a full length guard but they weren't the Gonelli Bultaco type. Now, the Gonelli is the only option for a green rear guard but fitting one without some sort of lower section will leave the back of the engine exposed to all the crud off the back wheel The middle exhaust box is a perforated tube and packed yes. I've never been into one of the TR77 type rear silencers but I've been told by those that have that they were packed with wire wool and have the two exit holes at the rear but underneath, not out of the end. Apparently, the mod was to rip out all of the wire wool, weld up the holes and put an exit hole out the rear as normal - but I've no experience of that so can't comment. What I did on my two MAR models was to make my own end silencers by using motocross / enduro back boxes, about 12" or so long, with the innards replaced with a trials size perforated tube (25mm in my case and straight, no bend) packed with wool. Keeps them quiet and the 310 in particular revs like hell.

I'm lost trying to understand what you've done You only loosened the allen bolts, you weren't able to remove them completely - which means you can't remove the tubes? But you managed to remove the seals with the fork tubes still in the legs? You removed the fork caps? If you unscrew the fork caps from the tube, they are still attached to the top of the damper rod and until you unscrew them from the damper rod you can't remove the springs. The usual process to fit new seals is to pull the tube completely out of the leg, so I don't know how you've removed and replaced the seals with the tube still in the leg.... Also, the allen bolts at the bottom of the leg house the damping adjuster which is a small brass screw head needle that screws through the allen bolt and into the bottom of the damper rod to control oil flow. If this isn't screwed right in before you use and allen key, you can damage the screw adjuster. If you don't have the tool to lock the fork internals the only way to remove the allen bolt is to use the spring pressure to stop the internals spinning. With the cap and spring fitted put the leg into the vice, then use a ratchet strap or something and compress the fork as much as you can, then see if the spring pressure will allow you to hand tighten the bolt until it just bites. If so, see if it will let you unscrew all the way. It should unless they were forced home and cross threaded or suchlike. The link below is to some instructions I put on some time ago for someone else asking for info on how to change the seals in a TYZ. http://www.trialscentral.com/forums/topic/27478-tyz-250-fork-seal-replacement/page__hl__%2Btyz+%2Bfork+%2Bseal

Check out insurance first because your premium could more than double with the modifications. Some insurance companies also want a certificate to the effect that the extra seats behind the cab seats have been professionally fitted and comply with safety requirements - ie they haven't just been fitted using 4 M6 bolts. Some companies won't insure you My last company, Commercial Vehicle Direct, wanted to increase my premium from £350 to £800 for extra seats and side window. I didn't renew with them and went with Adrian Flux who specialise in modified vehicles. They insured me for £360 with the side window and extra seats. When I was looking at changing the van a few weeks ago, I asked them for a quote on an unmodified van - £800..... the reason being they only specialise in modified vans, not unmodified... If I added the side window and extra seats to the SAME VAN, it was roughly the same as I'm paying now - you couldn't make it up. I found Chuchill to be very reasonable when I was getting quotes for a new van a few weeks ago. There was no premium increase if I modified a standard van with extra seats and side windows. They just asked for a certificate from a professional that the seats were fitted to a satisfactory standard. If you go onto ebay and search on van conversions, you should get plenty of pictures from the adverts

If he'd stayed at Tech3, Yamaha wouldn't give him the full spec bike he wanted. There was no room in the full factory squad and even if Rossi leaves at the end of 2014, Espargaro is waiting to take the place. He wanted a factory bike, he couldn't have one with Yamaha, he wasn't going to win a race on the Tech3 without a huge slice of luck. He may not win a race with Ducati but he has a factory ride and an opportunity to help with the development of a new bike. He's no worse off in terms of race winning opportunities but he's a lot better off financially. And there's always the chance that Ducati may create a front runner again.

He had traction control on his 990 Honda before anyone else. Burgess said that Rossi's first comment about it was 'this is cheating'. They also had early traction control on the NSR500, first tried out in Doohan's day along with anti-wheelie and active suspension. When he was winning his first championships, all of his opposition were 30+. He's now in the same position and the opposition is just faster.

The gearing I would guess as being standard. The original MK1 MAR used 12 : 46 which was changed to 11: 42 from the MK2 onwards. The two bikes I had back in the 70s were both MK2. They were pretty quick on the road, especially compared to the '71 Sherpa that I'd had before which must have struggled to get 50-odd mph (never had a speedo on it) The Ossa would see 75mph on the speedo flat out and in a drag race could beat my mates' (3 of them) Honda CB200 off the start up to about 50mph until I changed into 5th which was a big drop from 4th and then they pulled away. The gearing as standard was always a bit tall and these days I tend to run 10 : 42 instead of 11 : 42 as it gives a lower 1st gear which, with the heavy flywheel affect, makes it very difficult to stall and the clutch virtually redundant. The only problem with the 10 tooth sprocket is the chain can catch the sprocket nut, you need the nut with the boss on the inside which moves the actual nut outwards and keeps the chain away from it. FYI - I use Barnett friction plates in my clutch and these were a huge improvement over the suflex plates I'd used previously. Break drive immediately with no drag and hardly ever stick if the bike has been standing. Because the plates are Kevlar or suchlike they bite harder so can be run with less spring tension which makes for a lighter clutch action. I got them from Doug Elke in the USA but he seems to have disappeared now and I haven't yet found anyone else that does them.

Just come in from the shed after reassembling the engine. I managed to get a good shaft from ebay USA so that is now in the engine. The shaft I have with the weak spring is the only one I have with this larger spring - typically. The ID where it sits on the shaft is 25mm. All of the others are 20mm. Don't make a special effort to look for one yet Giles, as although I'll want one eventually, the immediate panic is gone due to getting the shaft from ebay. I'll also speak to Steve Sell this week as I'll be at the two Miller rounds next weekend and he usually rides one or both of them so if he has one he can take it with him. I'll let you know after that whether I still need one.

Retard the ignition all the way, put a flywheel weight on it and it too will become impossible to stall. It will still pull like a train but won't try and leap out of your hands when you touch the throttle

Hi Giles, it's the return spring on the selector shaft but there are two sizes, so I'll need to measure it when I next get back into the garage. All I know is it is the larger one for the shaft that has the larger diameter piece where the spring locates (rest of the shaft is the same) Not sure about the porting on the MK1 barrel but they had a smaller crank assembly so, I think, different crank compression and should rev up quicker. They fitted a larger crank to the MK2 and the rest from '74 onwards. I had a go on a green 250 recently and was surprised at how well that picked up off the throttle, a fair bit quicker than the MK2 version that I'm more used to

He probably got mixed up with the Sherpa S 175 which wasn't a trials bike but resembled the Lobito. He's definitely referring to the late 60s as he was suggesting Bultaco were trying to compete against the 175cc and other smaller bikes that were being produced at the time, mainly here in the UK. The model 221 was created as a holiday resort rental bike for various holiday destinations in Europe, I think 175cc because that was a restriction on engine capacity without a full licence in parts of Europe. Some were released as trials bikes. Basically a sleeved down 250, model 190