woody

Forks, MAR or Gripper I use between 180 - 200cc, usually 10W. Gear oil, yes, around 900cc on either. For plugs I generally use BP7ES in most bikes, never had any problems with them. I've seen the article on the Vitale bike with induction can. Never tried one on anything, but that is one ugly bike with all the mods... I bought a 250 Gripper many years ago that had a '74 reed valve Phantom barrel/head 'grafted' on. It was a mess (the fit to the Gripper, not the reed conversion) and didn't work well at all. Put it back to standard but it never ran right so I sold it. There's an article on the net somewhere about a 250 Gripper that Joel Corroy converted to reed valve using a MAR barrel.

With the Amal, make sure you're not running with the choke on. The lever works the oppostite way around to the conventional way - down is choke off, up is choke on. Easy to get wrong if you're not used to them and I've seen it done - someone rejetting their carb as it was running too rich but they were running with the choke on. Yes, a Mikuni is better than an Amal but if the Amal is in good nick the bike will run perfectly, the difference with a Mikuni will be minor. Mikunis are a nightmare to jet due to the infinite combinations of needle / needle jet pairings and there is no base setting from which to start from. With the Amal you will be able to find the right jet specs from somewhere so at least you'll know if your jets are correct. I'd only swap from the Amal if I was sure it was worn in some way. Gearbox, you can use a modern light gear oil such as Silkolene Light. For the clutch, David Taylor recommends Morris Lubricants Golden Film SAE 20 following advice from Kevin Breedon racing. Dave's son Rob has been riding a MH349 for quite a while which they have pretty well sorted and have found that this oil gives the best performance from the clutch. Or you can just use ATF as mentioned before. Synthetic 2-stroke can be used at the ratio you suggest, 50:1

Yes, with a pair of good shocks working correctly, the back end works very well and Ossa front forks (Betors) are very good too. Many people don't rate the Grippers. I jhaven't had enough time on one to judge really, I've ridden a few, briefly, but most have been dogs. The one I have now is the fieryest I've tried yet. I love the MAR but it stuggles against 80s twinshocks when sections get bigger or more technical. Maybe the ultimate would be the MAR chassis with Gripper suspension and 350 Gripper motor...

Assuming it's just the internals you're talking about. The actual damper rods are the same on both bikes, the holes drilled into the damper rod are identical but on the earlier Bultaco forks (around mid 70s models) the holes in the piston are different. The Sherpa has slots wheras the Ossa has holes and it looks to me as though the Sherpa arragement allows more oil flow. The 340 Sherpa has the same damper rods with the same holes but the piston is completely different from the Ossa and earlier Sherpas. It is just a solid square with round edges and I assume the oil just moves past the gaps at the sides of the piston. I never have managed to suss out exactly how the damping in front forks actually works. However, my thoughts on the Sherpa letting more oil through on the compression and rebound are consistent with the behaviour of both types. The Sherpa forks don't damp as well as the Ossa (subjective, my opinion) on compression or rebound for the same oil quantity/viscosity. I tried 5 - 30 weight in the Sherpa and nothing got them as good as the Ossa. Too soft on compression and too quick to rebound. Even with too much 30W oil in so that they hydraulic locked on compression, they still topped out on rebound (several forks on different model Sherpas, not just one set) After much messing with the forks on my 340 Sherpa I still couldn't get them right, gave up and fitted Ossa damper rod assemblies instead. Forks work as I want them now. About 180cc of 10 weight.

The old Ford Sunset Red is a good likeness, more orange-red than red. Don't know the RAL code but it was used on Escorts in the UK in the early 70s

Not yet tried an OKO on the Gripper so can't help with that specifically. I have one on the 350 MAR and it is fine but as the Gripper is ported differently I guess the jetting would be different. What I forgot to mention is the head spacer, as they come in sizes from 0.5mm (or probably less) to 3mm thickness. Not sure what would be standard. My 350 Gripper, which I bought to renovate, has so much compression I can stand on the kickstart at TDC and it won't go over (and I'm 240 pounds approx) It's an absolute bitch to kickstart and is quite fiery off the throttle. When I get around to sorting it out I think a thicker spacer will be required... Possibly, yours may have a thick spacer which will soften it off with the reduced compression. Bit of a pain to check but may be worth a look (assuming everything else is in order such as timing, etc)

The weights were standard fitment on the Grippers, both 250 and 350. From memory, you can't just remove the weight and leave the cushdrive as it's designed to fit together. I think you have to fit a complete cushdrive from a MAR to run a cushdrive without the weight. The spline that is a tapered fit on the crankshaft is a different length on the MAR. However, the 350 should have plenty of snap with the weight in place, if it's sluggish to pick up there's something wrong. It should be fine with the weight on.

If you want to replace the ball races in the headstock with taper rollers, Pyramid Parts have taper rollers that will fit. If you measure the existing bearings they will match them for you (I've replaced mine but can't remember the size) This is a link to their website page with the bearings by size. The site is a bit of a mess at the moment as it is a new one and they are still transferring stuff over from the old one. They haven't got their contact details on there yet but you'll probably find them through Yell.com. You can either order bearings by phone or on-line. http://www.pyramidparts.co.uk/steering-hea...earings-by-size

Venhill are probably the only cable supplier now. You can order direct from them but MAKE SURE you measure your front brake and clutch cables before you order from them as you may well find that their front brake cable is too short unless they've corrected it since I ordered one. They also had a bit of a mix up between 242, 330 and 350 part numbers (their part numbers that is) Better still, send the old cables to them so they can ensure they send you the correct ones back with the correct nipples either end and the correct adjusters. for the parts below, In Motion (Bultaco UK) should have them all Chain and sprocket set I think the front is on a taper and not the spline as its held on with a 24mmAF nut (any input would be nice) - Yes it is on a taper, the original also has a slot for a key but the replacement Talon one doesn't but the tasper is sufficient. Have fun getting the old one off... Rear brake cable this snapped years ago and was replaced with a rod which works but not correct - They have the cables for the 247 Cota so should have the MH349 too but a rod is probably better Carb rubbers both sides 1 Chain tube Chain tentioner pad Airfilter Fork seals They will also have the cables but obviously these are from Venhill and are what Venhill send them. I'd get them direct from Venhill so you can make sure they are correct. They may have a fuel tap also. If you search the Montesa or Twinshock forums you should find some advice on the MH349 clutch set up from Rob Taylor who rides one regularly and who very kindly lent me one to ride in the Bootle Classic trial after I broke my Ossa the day before.

I've used either Ford Diamond White or Ermine White. Diamond is quite bright but the Ermine, as used on Lotus Cortina and Twincam Escort is still a nice gloss finish but has a more creamy appearance and works well with the green stripe. Don't know the RAL code but should be easy to find. The problem is finding the right stripes. Most that are available on ebay or wherever seem to be the wrong green (too dark) or the wrong shape (like the Miller stripes)

You can also buy an original spec Dellorto from Dellorto UK (they'll jet it to whatever you tell them) Cost delivered is just over

Some had plastic, some had fibreglass. If yours is plastic it wouldn't have been painted from the factory, they were just the colour of the dye/moulding. It's more likely the paint has bubbled as someone has probably used aerosol paint on it. Modern paints are far more advanced than what used to be available and if painted by a professional who knows what they're doing with different materials, it should last - Plastic primer, elastic/stretch additives etc. I had a plastic Bultaco tank painted about 3 years ago and there are no bubbles. A mate's 240 Fantic has a tank that was painted more than 10 years ago - no bubbles. Personally, I think it is bad preparation and wrong type of paint that causes the bubbling rather than petrol fumes but that is just my opinion.

I don't think you can ride your GasGas though as it is a Sammy Miller classic championship round with the usual classic classes. I'd check with the club to be certain before you enter as I don't recall seeing modern bikes in previous years

Penny's just dropped what you mean as I was wondering what Midland Classic had to do with it... Reliance results are on a link from the home page, not the results page.

http://www.poacherspre65trials.co.uk/

http://www.southshropshiremcc.co.uk/

The rod length varies on different Sherpa models. Can't tell you the length of the 159 but Hugh's Bultaco, or whatever they're called now, should be able to give you the information/correct part. If you search either the Bultaco or Twinshock forums you'll find a very good article from John Collins on how to set the clutch up. It would be worthwhile looking this up to make sure your set up is correct. I'm pretty sure the pin type basket is correct for the 159. Again, Hugh's should be able to confirm. Also, make sure the pins are straight as some look a bit bent and off centre in the photo. If they are it will stop the pressure plate releasing correctly which will cause drag. They straighten easily if needs be.

Latest new is Nigel Birkett is due to visit the factory soon and Ossa UK will start 'operating' from August 2010 (importing?) So everything looks to be on course. Must talk to Nigel about an outstanding warranty claim on my MAR...

There is no packing in there, only baffle plates, so the most it could do is let out any oily deposit that has built up. In those I have cut open so far there hasn't been any, they've been dry.

Many times probably but a long time ago when it was a group used in Midland Centre road trials when we were allowed to ride on Clee Hill. Probably done a couple of Stourbridge trials there as well but again, 10 years ago or more. If it's the venue I remember it's a small rock bed stream which the sections wind in and out of with a few roots thrown in here and there. Nothing big so you'll be fine.

Tank fittings: The Gripper frame has two threaded bosses welded on just behind the headstock. The original one piece fibreglass tank/seat unit has a hole each side at the front of the tank. These holes have some sort of rubber bush in them and 6mm bolts fix the front of the tank either side by screwing into the threaded boss. The rear of the tank/seat unit has a clip riveted either side of the sidepanel which clips to the frame tube. On the UK bikes with the alloy tank and separate seat unit, the threaded bosses at the front of the tank each have a lug screwed in. Onto this lug is pushed a rubber mount which is circular and about 0.75" thick and 1" diameter (at a guess) same as fitted to a MAR. The alloy tank has a 'C' shaped bracket on the inside, both sides, which push over the rubber mounts. Like a TY250 Yam twinshock. The seat holds the rear of the tank. The UK separate seat unit/sidepanles have the came clip as the one piece tank/seat unit, although when the seat is bolted on it is enough to secure the seat unit without the need for the clip.

Mine has a crude device welded to the down tube drectly under the headstock with two stops welded on either side which engage the bottom yoke on lock.

If you mean the Stourbridge trial this coming weekend then you'll have no problems on the easy route. They won't have anything daft in it.

In the first section but not all the way up to the box, only up to the point where it is level with the front of the shock. The box has baffles in it - about 7 of them as well as a cross over from one side to the other. It's unlikely you'll need to open this up.

I've heard of a few people having problems getting IRC to stay inflated, but only on the 2010 Evo, nothing else. I've just fitted a new IRC onto a new older style Morad rim with no problem.