woody

http://www.rexcauntracing.com/ He never actually lists the Ossa springs in his products category for some reason, normally you can find them in his ebay shop but they aren't listed there either at the moment. He definitely sells them, may be out of stock at the moment. Contact details are on the website if you want to ask him

Yours is correct, the other one has been modified by cutting off the bottom frame tubes and fitting the bashplate. It's done to gain a little more ground clearance

Found the wheels To measure, I put a long ruler across the hub with the brakeplate removed so it overhung the edge of the rim and then measured the distance to the rim (the flat side of the rim rather than the little lip that runs around the edge as not all rims have that lip) Front offset is 22mm Rear offset is 68mm

A rear MT43 is an acceptable tyre in terms of providing an adequate level of grip but it's old technology so it is not as good as a modern Michelin/Dunlop/IRC in any conditions other than snow or ice where its harder compound bites in better. Same for the front really - they'll grip ok, but a Michelin is probably the best all rounder on the front. In the end, depends how serious you are as to how much you want to spend. The pirelis will be adequate, no more.

I should be able to help with the wheel offsets but not until the weekend, I have a pair of 240 wheels but at the back of an unlit shed underneath loads of other stuff - unless someone else provides them beforehand Why not just fit a new standard spec Delorto - not sure what the prices are in Australia but here they are a bit less than a new VM Mikuni at about

too right - he'd reverse the charges

I don't mean to jump down anyone's throat here, each to their own and all that, but why is there a need to find a trial that has a class for a type of bike. Surely, you ride the type/make of bike you enjoy riding and just go to a trial and ride it. Most clubs have at least 2 routes now, many have 3 or 4. Just ride it on the route that suits you and that bike. If there is no aircooled mono class just enter whatever is appropriate for you - clubman, novice o/40, whatever. It's what I used to do on my Ossa long before the various pre65/twinshock series sprung up. What's it matter if there is no specific class. Never can understand this. Only time it matters is if an event is for a specific type(s) of machine or if it is a championship for specific type(s) of machine. Then obviously you have to comply. Normal club trials cater for just about anything these days. Some classic clubs tend to try and keep more modern bikes out. Don't know how old you are but couldn't you ride one of the over whatever on modern bike classes at Bath

Assuming you're using the Jap kill button with two wires, one goes to the larger spade terminal on the HT coil (should be the blue wire from the stator if it's original wiring) the other to earth.

You don't mention ignition timing - have you checked that

Michelin x11.... It's easy enough to rip the knobbles off those on a trials bike, never mind a KTM - brave lad.... Anyway, the tubeless rims like that on your Gasser, are about

Which tubeless tyre are you thinking of running on a KTM - enduro/motocross tyres are tubed and the tubeless ones they were experimenting with are completely different from trials type. It's usually only the Pirelli MT43 that riders use on enduro bikes and that is tubed. It's a hard enough compund/construction to put up with the abuse an enduro motor will give it. The tubeless trials tyres are modern soft construction and I would think they'd be shredded in minutes on an enduro bike. A rim lock isn't required on tubeless rims and once you've drilled the rim to fit one you're going to have to fit a tube as it will no longer seal....

If you want to be fussy, the 85 Alpina frame doesn't have bolt on footrest hangers like the 80 With the 49, depends which 49 frame you're referring to, there are 3 types and only the last type is the same as the 80 (excepting tank, seat and sidepanel mountings as mentioned) First type the shocks are more upright and there is only a single tube under the engine Second type has the shocks repositioned but still only single tube under engine Third type has two bottom frame tubes with wire mesh between, like the 80.

Magical has one leg longer then the other...

Montesa Cota 247 and Ossa MAR both use a spindle attached to a right side pedal which runs behind the engine through bushes in the frame plates by the footrests which then operates a rod or cable on the left side. The Montesa set up is better as it uses an arm attached to the left side of the spindle which is then connected to the brake arm on the wheel by a rod or cable. The Ossa's is a slightly more tortuous affair where the outer cable is used as the actuator rather than the inner cable - definitely not worth copying. I think Sprites have a spindle arrangement too.

With that sort of form there's every chance he could go past 7 wins - hard to see anyone who can match that ability - stop or no-stop rules

Yes, whilst dished sprockets were still around Keith Horsman made a very neat bearing carrier that bolted onto the dished sprocket which gave support to the spindle. You ended up with 4 bearings on the sprocket side of the wheel. The spacer used with the flat sprocket conversion also acts as a bearing carrier.

The bikes had a nice dished sprocket as standard. An alternative aftermarket conversion was to fit a spacer to extend the hub and a flat sprocket. This was generally a Sammy Miller conversion, not sure if anyone else did it (in the UK) With the dished sprocket, there was a long spacer between the sprocket and swingarm and as the spindles are only 12mm and a bit soft, the pull of the chain could bend the spindle slightly where it was unsupported. I don't know whether the flat sprocket conversion was to cure this or because it was cheaper to produce than a dished sprocket - or both, although pattern dished sprockets were produced as well by some companies. Dished sprockets have been unavailable for years now, but finally they are being reproduced in Spain

Found it thanks - reason I completely missed it is because the clutch arm is located incorrectly and at the wrong angle. It's pointing forwards so the end where the nipple fits is way in front of the locating lug in the bottom mount. Easy enough to put right at least. Thanks for your help.

The 23 prefix is generally a MAR from 1974 - 76, in other words the MK2 MAR. They would have matched from the factory, I'd say you've mis-read one of them in view of the fact that they both end 300, but obviously, a 35 year old bike could have had an engine swap and as a coincidence, they could be similar. Look here - http://www.ataq.qc.ca/galerie/index.php?fo...=/Mus%E9e/Ossa/ Yours would be the 1974 model as produced by the factory - for the UK the fibreglass tank was changed to an alloy one by the UK importers as fibreglass was outlawed by then. One of the nicest looking trials bikes ever made. Lots of info on this site too http://hem.passagen.se/ossa/

He moved to the 360 in 1980, using both that and the 200/250 and became a full Honda works rider in 1981, winning the championship in 82, 83 and 84 on the 360. In 1985 he had the monstrous looking 360 mono RTL but changed to the 250 (or 270) in 1986. 1987 was his last year on the Honda. I'd guess as he was a Honda factory rider that his bikes weren't UK registered. Rob Shepherd and Nick Jefferies' twinshock 360s were as they rode for Honda UK. It was one of the UK bikes that was tested in TMX. Maybe someone has some pictures from UK world rounds or SSDT showing the registration number. May be some in the Four Stroke Finale book.

That GOV 132 is a replica anyway built when Sam was riding Pre65 events The real GOV 132 had two incarnations according to peeps in the know with set ups for radically different conditions. As good as it was in its day, today's replica Ariels would destroy it in competition. A mate of mine has a nice HT5 with lightweight frame and all the other usual goodies. He tried Martyn Willmore's bike and was ready to throw his in the bin afterwards as it is light years away, it really was that much better - Martin's bike is Mick Grant's old bike, so imagine what Mick's new bike is like...

Definitely, and that's the difference between the British stuff and the twinshocks - the Brit stuff reliability is plain awful and there is every reason to update components to make them work as they should in order that you finish an event rather than push the bike back to the van. Twinshocks, right from the first Bults are reliable right out of the box, although modern electronic ignition is favourable on anything over points......

I agree with you in principal about the engines BUT, what do you do if someone fits a reed valve to their 240 motor. There is nothing wrong with that. Reeds have been around a long time, TY Yams had them in the 70s as standard fitment, UK specialists were fitting reeds to Ossas, Monts, Bultacos in early 70s onwards. To police it is next to impossible as unnless you know your stuff the engines all look the same. Same thing applies to having diiferent classes for Pre72, Pre80 and Post80. Who has the knowledge to scrutineer and date and place a bike in its right class and which clubs have the manpower to do it anyway. Does that 72 Bulto have a 340 6-speed ftted, has that MAR got a 350 Gripper motor with the fins shaved? We're reliant on riders being honest and in the main, most people I know who ride in the Miller, Traditional and other main classic events, don't want to modernise their bikes beyond 'acceptable' - subjective I know but most are in favour of not modernising them out of context. A 200/240/300 Fantic is the benchmark for twinshocks, in my opnion that is. Unfortunately there are some advocating that standard twinshocks aren't good enough for current twinshock events which is convincing some that they need to modify their bikes or they are uncompetitive - this is of course complete B*****ks as the sections aren't anywhere near as hard as a British national of their day. Saunders could lose around 20 odd marks on his Armstrong to win an event back then. I'd be over 100. If I'm losing about 20 marks in a national twinshock round now on the same kind of bike, he'd clean it with his eyes shut - the bikes are more than capable of handling the sections. Sure the older twinshocks have a harder time of it against the modern twinshocks - clutches are nowhere near as good, brakes aren't (apart from KT250) they are unstable under clutch./brake riding but - that's what they are and we either enjoy riding them for what they are or buy a GasGas

They aren't that modified really Kev Nolan's Jumbo is standard apart from a set of Paioli forks as the original forks were scrap. They obviously aren't period and whilst I'd prefer a ruling that specifies period parts, it's debatable whether they offer any real advantage over a set of period Marzocchis Phil's Fantic has head angle and footrest position altered, neither are necessary, it's just personal preference really. OKO carb fitted - can't say that these offer any benefit over a correctly functioning original carb. I've tried a 240 Fantic with OKO set up and it was no different or better than my mate's standard bike with an unworn dellorto. He still has the 300 motor as far as I know and and also as far as I know there are no other mods. David Pye's Fantic I don't know much about but I'd guess it has same type of frame mods as Phil's but it may have a later engine - can't say that this would give much of an advantage as very very few sections are about power. Ian Baker's Honda is Classictrial prepared so the mods are documented on their website. Whilst I'd agree that some of these mods improve the bikes, the improvements are minor as opposed to what you see in Pre65 where the improvements are a quantam leap to the point where they are no longer recognisable as the original marque (I'm not saying this is wrong) The twinshock mods are generally in keeping with what could be done in their day if a rider wanted to and are more down to personal preference rather than radical improvements. None of them offer any significant advantage over a standard Fantic 200/240/300, Armstrong, Aprilia, Garelli etc. but obviously they are all far ahead of a 70s bike, even a modified one - why I think there is potential for year breaks for twinshock class. I'm in no way against mods like these obviously, it's part and parcel of machine ownership, but I really wouldn't want to see the day when we have modern T45 replacement frames, lightweight billett hubs and yokes, frame kits for later engines etc. To me, riding a twinshock is about riding a particular bike you enjoy riding, not turning it into something it never was or could be 25 years ago. What I meant before when I said they are perfectly rideable was that they don't ride like a pig as does your typical standard Pre65 bike, they are capable machines, but that's not to say owners shouldn't personalise them to their own riding styles. Disc brakes thankfully are outlawed and hopefully will remain so. I can think of a few sections in recent trials where a disc would have been a huge advantage - unlike the mods above.

No they wouldn't - why do you think they modify them - have you ever ridden a standard HT5 Ariel All those twinshock variations you mention are prohibited by the national championship rules. Unlike pre65 bikes, twinshocks are perfectly useable in their standard form