woody

Just had a look at your rules and have one or two genuine observations. Twinshock minimum wheelbase 50" - TY175 and mini-Majesty and possibly Whitehawk are less than this. Forks max 36mm - Why 36mm all were 35mm apart from SWM at 38mm. Is it intended to allow Yama Mono front ends (which I don't have an issue with as Yam monos were competing against twinshocks in 1983/4/5 so it was a possible mod then. 38mm Forks - it's a bit woolly. Can only SWM use them or any twinshock. As there are no dating classes in t/s, it's one class that spans 1970 - 1985, therefore it stands to reason that any bike can have 38mm if they are all competing against each other? Maybe needs rewording to clarify exactly what the rule means. Fuel carried in tank above the motor - There is a genuine Bultaco modified in the 70s by Steve Wilson that had the fuel tank and air filter positions reversed (like the later JCM) John Collins owns it now and still rides it. It was ridden in the 70s like this but by definition would be in the specials. There could be other bikes out there like this as people were creating all sorts back then. If someone copied that Bultaco now, does it make it a trick/cheat/special? Tubeless rims - I've said my bit on them... Later engines - How much of an advantage are they, really? It's mainly Fantic or Beta we're talking about. Again, I'm not keen on it but have no real objection. If I fit a 240 Fantic with a reed valve it is perfectly acceptable. Tamaha TY250 had them in 1973 as a production bike and set a precedent. Ossa UK were using them in 1975. Numerous privateer bikes were converted in that era. So there can be no objection to any twinshock (in the absence of cut-off date classes) being fitted with a reed. So, back to the Fantic. What is the difference between me fitting the reed to the 240 or putting in a 245 reed motor which saves me trying to find someone to convert the 240 for me. I can't see any. I also wouldn't bother I have to add, as the Fantics 200, 240 and 300 have more than enough GO for today's classic sections - see previous post. But if some choose to do it I'm not going to object. If I had a Fantic 240 and put the latest 307 motor in it, I'm not suddenly going to win this year's Normandale championship. My results will be the same. Similarly, if David Pye removed his 38mm forks and later motor and put his 300 back to standard, he isn't going to drop behind me in the results. I can see what you want to do and that you have concerns over the direction you think twinshocks is heading, but I see the reality differently. I don't think it will ever go the Pre65 route. Even the oldest twinshocks are quite reasonable to ride in terms of handling, weight, steering and suspension. Even the worst of them like the KT250 (sorry KT, I loved you but you weren't the best ride) is still competitive in a modern B trial and I actually won a few B standard modern club trials on it, against other twinshocks and modern bikes. So there isn't the need for them to be heavily modified to make them rideable like a god-awful standard Pre65 bike. These 'super' twinshocks don't really exist. Most of the mods are cosmetic and remodelling, performance wise they aren't putting those bikes light years ahead of the standard machine - like in Pre65 Things can always change I guess but I know from competing all over the place that most riders agree on where the boundaries are. There will always be one or two who want to 'push it' but that is human nature - in all walks of like.

The bloke is bound to say this though isn't he as he is selling the product and has to justify it. Interesting as he was one of the biggest critics of modifying twinshocks not too long ago... Honda TLR forks aren't as good as Marzocchis in my opinion as they are like most Jap forks, under sprung and under damped. Fairly easily rectified if needs be by reducing the oil flow by reducing the hole size in the rod and fitting uprated springs or more preload. All depends on your weight and what you want. Nothing that wasn't done back when they were new. Shirty used to modify the Majesty forks for supported riders for the same reason. Normal customer bikes were left stock. As for TLR foks not being suitable for use in 'serious competition', what is 'serious competition'? 38mm forks will give you no advantage whatsoever in your average classic event. The severity of sections is nothing like the sections these bikes were ridden over when they were new. In today's classic club events the suspension oil barely gets warm compared to an early 80s trial. Ride your twinshock in the SSDT (like David Pye) and there probably will be a benefit over long, big, rocky sections and continuous moor crossings. But you need to be a rider of his calibre to notice. I doubt I would. 38mm forks are not needed for classic events, the suspension doesn't get worked hard enough. Probably 90%+ of people riding twinshocks in classic events today couldn't get the maximum from a 1970 Model 49 Bultaco in standard spec. When they can, then they can claim fitting 38mm forks gives them an advantage. Personally I'd rather see twinshocks not fitted with them but I don't object to them for the reasons above. I know 38mm modern forks can sometimes be picked up for less than the cost of rechroming originals (as I'm just having some done now -

Assuming you bought the same size as I did when I replaced them in a 247 and MH349 they are a straight replacement, no spacers needed. edit: can't remember the size as too long ago.

Exactly, I wouldn't disagree with that. The question is 'why are the bikes modified in the first place?'. Because they were not very good. Backed up by the fact that everyone dropped them like hot bricks once the 'Spanish Three' arrived. I'll hazard a guess that Pre65 started up in the 70s because riders who were no longer competitive on contemporary machines still fancied a ride out on the bikes of yesteryear as a bit of nostalgia. I'm guessing, not stating as a fact, but all trials were single route back then, so it's possible that if they couldn't cope with the sections, thie older bikes in older style events were a solution. Fast forward to the 80s and a few more riders who started on British bikes in the 60s and who may no longer have enjoyed modern trials, move across to Pre65. Around 1984 the Pre65 Scottish was born. The problem now is that most of the riders have ridden much more modern and capable bikes and so starts the modernisation of the British bikes which must feel horribly antiquated by comparison. Add to that Sammy Miller is riding his further modified Ariel and away it goes, people need to modify their bikes to sta competitive. The rest is just natural evolution into what it has become today. I've said it before and been slated but I'll say it again. If modified bikes were banned I think you would see a huge reduction in the number of British bikes being used as not everyone wants to ride a standard bike. Some are just awful. I remember Rathmell being asked about riding a Greeves in the Pre65 Scottish and he said no way, they were crap then and they're crap now, why would I want to ride one of those'. I can understand people wanting to modify them. Times change and almost everyone has experience of riding bikes newer than the original British bikes. I imagine not many want the authentic experience of dodgy electrics, worn out or inefficient carburettors, suspension that doesn't suspend, inefficient and noisy exhausts, lethal footrests and probably the biggest issue - the weight. The modifications make the bikes easier to ride, more manageable and much more reliable. The Pre65 tag is just a label, a class name - does it matter what it is? They are still British bikes in essence but no longer to Pre65 specification. Again, does it matter? The one thing that really p****s me off about it is the hypocricy with the regs. The silhouette philosophy - you can use brand new replica parts, frames or billet components, as long as they resemble the original.... How many of the modern parts deemed acceptable resemble parts from before 1965? As for the silhouette, how do any of them resemble the original form? Now I don't have a problem with this as I own a BSA which is being modernised, but I really get wound up at regs that allow brand new parts to be used that look nothing like the original, but prohibit the use of cheap alternatives from broken up old twinshocks such as wheels, forks, hubs, yokes which could be obtained at a fraction of the cost. It's regs such as these, spawned mainly from the Scottish which are forcing people to spend thousands if they want a bike to compete at top level on. Such a bike could be achieved at a fraction of the cost with used parts. But you can't because they 'don't resemble the originals'. Well, unless you have seriously distorted vision, neither do the parts that are alllowed. The modified bikes aren't the problem. The idiotic rules that abound are.

Tam, I'm not deriding what you're trying to do, definitely not. My reply was genuine. You mentioned 4 simple rules, one of which was no Jumbo forks, another was tyres to run with tubes. Jumbo forks was a bit loose in its definition, hence my comment. Tyres to run with tubes is also a bit loose but infers no tubeless. There seems to be a growing trend in outlawing tubeless tyres on tubeless rims which I can't honestly understand. You may consider tubeless with a tube in ok and I have done this myself, but not all tubed rims will support tubeless tyres, therefore that combination is not always possible. I've detailed previously why I've moved to tubeless on my bikes whenever possible, my BSA included. Believe me, if the tubed tyres performed as they should I wouldn't have bothered to incur an unecessary expense. However, tubeless also make it a lot easier to deal with punctures so that we can enjoy doing what we like best - riding - instead of wasting so much time with patches or fitting another tube in the middle of nowhere. There is a simple answer to the Pre65 'dilemma' if organisers want to do it. Taking a C15 as an example, if the bike doesn't look like the picture below and retain its original parts it goes in the specials class. As I said before, it's not hard to judge what is and what isn't... Personally I think the horse has long gone and it is too late to stop the modification of British bikes. Some do it for the enjoyment of it, some because they can, some in the misguided belief it will turn them overnight into a champion of the class. It will continue. However. there is nothing to stop individual clubs holding events for standard machines. Make it VERY clear in the regs that anything considered not standard at the organiser's discretion will go in a specials class. If people want to enter such a trial on their standard machines, they will. Too simple? Seems a logical enough concept.

If you really want to 'pep it up' a bit, the cheapest and most effective way is to fit a single crank weight from a 250 in place of the double weight on the 325, or a 250 ignition flywheel which is almost 2lbs lighter. Or both. It will pick up very quickly / very very quickly...

What are Jumbo forks? The last model SWM had 38mm Betor forks so if you mean 38mm diameter, that is a period twinshock dimension and you would ban a standard SWM with that rule. Better to say no 38mm forks dating from post 1985 if you want to prohibit them. However, having ridden a few bikes with modern 38mm forks fitted they offer bugger all advantage as far as I'm concerned over a well set up pair of standard Marzocchis. As far as defining a proper spec British Pre65 bike, by definition it should have no electronic ignition, Monobloc carb, steel rims, steel hubs, original forks with no modern internals, original yokes, no modern rear dampers, steel (or alloy?) mudguards, original footpegs, steel fuel tank, steel oil tank and weigh over 260lbs. That's a pretty accurate Pre65 spec. Any deviation from the above puts it in a twinshock or modernised class. You may have to concede to modern tyres but Bridgestone or Barum trail type could be used to mimic the performance level of 60s tyres. Not being facetious with this but you asked the question, that's a genuine response. Finally, what is the obsession with banning tubeless tyres on tubeless rims, even on twinshocks. There is a good reason they are used and that is because the tube type trials tyres on sale aren't too clever. The Michelin Radial is as effective as a Michelin Pilot in mud and you may as well leave your bike in the garage as fit one of those. The IRC tube tyre is of dubious construction and inconsistent in its performance at best, some are ok and some aren't. They're prone to punctures, particularly compression if used hard, soft sidewalls that roll all over the place on rocks and cambers and the support wires can break through on the inside. The tubeless tyre is much stronger in construction, they are no better in terms of compound or grip, but they don't suffer the aforementioned problems. Unfortunately, they can't always be trusted to stay seated on a tubed rim fitted with a tube and may drop off. If they do - trial over. For someone like me, who travels long distances to take part in trials all over the place, there is no way I'm going to spend hundreds of pounds on travel, accommodation, fuel, entry fees, bike prep. etc, to have my day ruined and all that time, effort and money wasted, due to problems with a tyre that a manufacturer can't be bothered to put right and seems to refuse to accept has a problem. They've been like this for 15 years and they've done nothing to correct it when all they have to do is make it the same construction as the tubeless. So, given the doubt that a tubeless tyre will stay seated on a tubed rim if worked really hard in more demanding events and having suffered way too many punctures and roll around sidewalls, over the last 2 or 3 years I've fitted tubeless rims to my bikes as and when funds allowed. This is so that I can go and enjoy riding with peace of mind that I'm not going to have my day wrecked by a dodgy tyre. The ACU have no rules that probhibit them in their series and if individual clubs start banning them I'll just turn my back on classic events and ride my twinshocks in modern events. It's the bikes I enjoy riding, as long as there are events to ride them in I'm happy - if they are all modern it's not a problem, I ride mainly modern events anyway. I just don't see the problem. Most of the moaning about modified bikes is the appearance, understandably so. Well, a tubeless tyre is black and round and indistinguishable from a tubed type. You have to look hard to even notice a tubeless rim. Does it really matter if you can't 'push the valve in' or there aren't any security bolts visible. A tubeless tyre is the only modern component that exactly resembles it's 60s counterpart, yet it's not accepted when modern billet machined parts that look nothing like readily are... It's just a tyre.

Coincidentally, we measured the ports on a Model 159 barrel and a 340 barrel recently and whilst I wouldn't claim it to be accurate to the nearest thou, they seemed to measure up identically. I think you're looking for something you don't need. Any 325 Bultaco has more than enough power. The best way to ensure it is running at it's optimum is make sure the carburettor works correctly (ie: it's not knackered or incorrectly set up, regardless of which type) and that the exhaust is repacked if it needs it. You could remove the baffles from the rear box and make it straight through like the earlier banana type silencer. Make sure the ignition is in good order.

other one

Picture added

Now that one I can't answer. My own preference is that my bikes look pretty near to standard as they are the bikes I liked when they were new (and I couldn't afford a new one) Certain aspects I never liked such as the thick seat padding on the Bultacos and Ossas and I always changed the seat for slimmer ones if possible. I hate the flanged rims on the older Bults and Ossas and changed them if possible. But I've never wanted to alter the appearance completely, colours and trim maybe, just to personalise it (once repainted an Ossa blue - disaster, but I was 17 at the time...) I agree that if appearance is changed radically people will think straightaway - trick bike, without actually looking at the reality of what is there.

True enough Hamish, but the reality is it's only the style of the bike that's different and it could have been done (rear mudguard excepted as it's Beta Zero - forgot about that) It's not a new frame from titanium or T45 or whatever, it's the original frame modified. The person that built it actually modified an Armstrong similar to this back in 1989/90 to ride in the Sebac championship (that bike is still around) It also has a later engine but any engineer could have increased a 212cc Beta engine to 240cc and fitted a reed. Arthur Browning made his 325 Bulto into 370cc using a huge Maico (or KTM) piston. Yamahas were using reeds in 1973 and Ossa in 1975. Bikes have always been modified, MacDonald Ossa from the 70s, Works UK Ossas with reed valves from 1975, Steve Wilson's Bultacos (one of which is owned by John Collins now) Rathmell's white 349, Vesty's and JR's 340 Bultacos etc. In fact when you look at JR's Bulto it was arguably more altered than this Beta but still looked like a Bultaco as it retained the most recognisable features in the tank and seat. The frame mods and swingarm mounts were extreme though.

Haven't got a definitive answer or RAL code but the old Ford Modena Green (as used on MK1 Escorts) is a very good match, based on the colour from brochure pictures. I'll post a couple of pictures of the colour when I can, one in, one out of the direct sunlight for comparison. For some reason, I can't at the moment.

The bike is a 1982/3 Beta TR125 twinshock, absolutely not a modified mono. The frame has been lowered and slimmed around the middle and the head angle altered (sounds minimal but actually involved an awful lot of time and effort to get that look) Only modern parts are the yokes (no performance advantage at all, used just for looks) and a 240cc engine to replace the knackered 125. There is nothing done to it that couldn't have been done back in its era apart from the motor. But in reality, if riding in classic/twinshock trials, the motor will offer no advantage at all. A standard TY175 can be ridden competitively in virtually all classic events including some Normandale rounds. Power isn't an issue or advantage in classic events. In addition to twinshock events, this bike was going to be used in modern B route trials, which is where we do most of our twinshock riding. A bit more power is useful in these events against the modern bikes.

I've sent you a PM so hopefully you have it. I've deleted some of my old messages, maybe there were too many to receive another.

Paul, it was built with the intention of being ridden by someone we're trying to coax back into twinshocks but could also be for sale (it's not my bike, nothing to do with me) If you're interested PM me and I can put you in touch with the owner and/or tell you a bit about it. It was assembled literally the day before the show, just in time to get it there on display, so there are still one or two little jobs to be done and then it is ready. I'm just going out, so be a few hours before I'm back.

That's not the same bike, the one on Wobbly's is priced higher than that Difficult to understand the

The bike is a 250 modified in the same style as Vesty's last 340. Not an absolute exact copy but close.

The Dellort on on my Bultaco has the 36mm inlet stub. The inlet rubber is 40mm I/D onto the manifold and 36mm ID for the carb. I don't know if this is the same as a 348 Montesa item though.

On the relevance issue, the trial was no-stop last year, so the number of entries indicates that the riders aren't put off by it being non-stop as they've returned this year knowing what to expect. That makes it relevant.

It's a strange comment Pete, although I think I know what you mean. Despite a full entry, certain factors such as extreme weather on the day of the event could turn it into a disaster - but that's a different issue and nothing to do with the format or organisation of the event. The 'success' comes from the fact that riders enjoy the format of this trial, they return the next year and the event enjoys a very healthy entry in terms of number of entrants. In that respect it is a success, surely. Money doesn't come into it.

Haven't been able to speak to Colin but this is his email address - leese898@btinternet.com

Didn't see this topic before as don't generally look into the Honda forum. Yes, it's a mate of mine at TY Offroad that does/did them but he's discontinued his website now which is why you can't find it. He'll be at Telford this weekend but not much use when you're in Australia... I'll ask him if he still does them and reply om here. Be tomorrow now though.

There's no membrane in the trials shocks Lee, oil and gas sit in the same chamber. If you touch the valve stem even for a split second, oil will come out with the gas. They are different from motocross shocks. They are straightforward enough to take apart and refill with oil. I can't remember the quantity but you can get it through trial and error. You won't have lost too much through the valve. Removing the damper rod assembly is a bit fiddly as you need to tap off the seal holder carefully with a drift of some sort as it doesn't screw in, it's a press in fit. Then you need long nose circlip pliers to reach the second circlip which is down inside the body, the first circlip is right at the top. At a guess, as it's a long time since I did mine, top up the oil level to about 3/4 full. Then refit the damer rod, turn the shock upside down (as it sits on the bike) and push the damper rod in. There shouldn't be any free play caused by not enough oil and the piston travelling though an air gap, nor should the piston hydraulic lock through too much oil. It's trial and error getting the level right but doesn't take too long. You can fill with air, it doesn't have to nitrogen in a trials shock,they work ok with air. A mountain bike shock pump from Halfords for