woody

I think it is the flatslide they can't have as the roundslide Dellorto is a contemporary carb that was fitted to 70s and 80s twinshocks Unless their rules have changed again...

I have a Dellorto on my 340 with the step down rubber but I don't know if it is a Montesa one or not to be honest. I don't know what size it is either as I've never needed to measure it but the carb is a snug fit. I will be doing some final fettling on the bike sometime in the week for the Normandale next Sunday, so I'll measure it up then. As far as I can recall, Dellortos do have differing inlet stub sizes as I'm sure I have one from a GasGas lying around somewhere that is smaller than other carbs. I have a 28mm OKO on the other 340 and that performs well too.

You can also get a step down inlet rubber which will fit the Dellorto/Mikuni/OKO inlet stub. Bultaco UK should have them. Saves the job of making the sleeve.

Incorrect - doesn't matter if your foot is outside of the section boundary.

On the flip side, I've known people MIG snd TIG weld bikes with electrics still connected with no adverse affect. I wouldn't do it though and always disconnect the wires for peace of mind (although I haven't a clue what's actually happening in terms of current etc. - don't understand electricity....)

That has been going on for a long time in the SSDT and other no-stop nationals. You see a top rider coming up a rock strewn stream, they get off line and the front wheel sogs into a hole or comes up against a hidden rock under the water. The bike stops dead and the rider is momentarily tipped forward over the bars, but still feet up on the pegs. They recover very quickly and manage to jink the front wheel away from the rock/hole still feet up and carry on. Very skillfull but they lost control, got off line and stopped. It's a 5 but they get a clean. Then Joe clubman comes up the section, makes the same mistake, bike stops dead. The rider doesn't have the same skill or fitness as the top rider. They hit the hole/rock, bike stops but a foot goes down as well. The effort to free the bike is more obvious and they get a 5 for stopping - correctly so. But they get penalised, the better riders rarely do.

Yes, because it's not consistent throughout the whole trial is it. Rider A stops feet-up on one section and gets away with a clean, Rider B has a genuine clean. Rider B stops feet-up in another section and correctly gets penalised a five, Rider A has a genuine clean. That's a 5 mark gap opened up instead of them still being level. If those two riders are challenging for the win, it makes a difference.

Don't know why you're even asking the question - the bike stops forward motion about 3 times in the first 10 seconds Doesn't matter how long it stops for, it stops and isn't a non-stop attempt. That section couldn't be ridden non-stop.

No, my mistake, I was forgetting the 200 has the clutch on the opposite side from the 247/348/349/330, so what I said wasn't much use for the 200...

Biggest problem with the older Dizzy is the both the bigend and timing side crank bearing are bushes. They're considered a weak point. Others with more knowledge of why will better explain the reason (as far as I know conrod kits are hard to come by as well) A worthwhile mod when rebuilding is to upgrade these to needle rollers. Alpha Bearings did mine when I rebuilt it and it never gave any trouble. Obviously you're not going to know the condiion of them without stripping and inspecting though. I thought mine was ok and it let go the Sunday before the Pre65 Scottish. That was a frantic few days in the shed and no mistake, including one 5am finish and one work all through the night. I finally finished it at 2pm on the Thursday, got everything packed up, bike into the van and was in Kinlochleven just in time to sign on before 9pm. Never ever want a repeat of that... The engines perform well as a trials engine with the standard head and road cam. Road gearbox is fine with the correct primary gearing. Triumph 500 (69mm) or 650 (71mm) pistons can be used to get them out to about 275cc for a little bit more torque, not massively different but worth it if you have to rebore anyway.

I don't understand what you're asking now ? The parts diagram is correct, why would you think it isn't? The spring fits behind the drive ratchet gear (2) and sits in a recess. The spring pushes the gear outwards and engages it with the kickstart idler gear (10) The spring cannot be seen in the photograph, as mentioned in a previous reply. If the spring sat between the two gears it would keep them apart, not push one onto the other. The kickstart return spring returns the shaft and as it rotates, the cam on the ratchet gear engages with the guide (4) and slides the ratchet gear back along the shaft disengaging it from the idler gear. Unless the shaft has been assembled incorrectly it's hard to imagine how it could be causing the engine to lock up. There's not much to go wrong with them.

Your links can't be viewed unless a person is a member of that forum. You can either put the pictures on a photobucket and link to that or become a site supporter and that will allow you to show pictures in your post. I can't really follow what you mean with the gear selection. It sounds as though it is selecting ok but if the lever doesn't return then generally the selector spring isn't fitted correctly or is broken. Sometimes the gear shaft can be bent slightly, enough to prevent the spring returning the lever but not enough to prevent selection. Presumably, when you are selecting upwards from neutral, you have to return the lever yourself before selecting the next gear. Not sure it is possible to just keep going up without centering the lever each change otherwise it doesn't re-engage the pawls in the drum for the next selection. The selector itself works by pawls which engage in the drum. If these get chipped, generally it means no selection at all as the edge of the pawl that engages and moves the drum are no longer there. The picture below is from a 330 Montesa which I think is very similar. The pawls are behind the round plate with the 4 screws and you can see the selector spring to the right of that.

For oil quantity start with 160cc and take it from there, adding 10cc at a time if more is needed. Maximum is about 180cc I think, any more than that and they'll start to hydraulic lock. SAE is down to personal preference but 10W is most common grade for older bikes. You may want to try heavier as the damping and springing on these bikes is fairly soft.

If it is Halfords' own paint, be careful what you paint with it as it does not like petrol at all. If you spill petrol on it, it can ruin the finish. Have you tried Steve Goode for Italjet manuals etc. He has some Italjet stuff.

As above, not worth it. In terms of performance I practically guarantee you won't feel any difference going from 325 to 340 - much the same as going from 320 to 340 on a Majesty. If you're on the last oversize on the 325 bore then yes, it's probably a cheaper option than having a new liner and going back to standard. 340 pistons are pricey now if you can find one. The 340 uses an 85mm piston from the 360 Pursang (which has a dfferent stroke, hence 360 not 340) Early 325 engines from M92, 125 and 151 can't be overbored as the liners aren't thick enough, they were basically overbored 250 barrels. The M159 onwards had the thicker liner.

Maybe I have but my comments are purely from what I see travelling around, although as mentioned in previous post I don't do YC or Red Rose so no idea how well supported the big bangers are there and I haven't been to Golden Valley or Bath events for some time. As regards classic green lane trials, I've never heard of them and don't know what the concept is. Hopwever, it sounds as though they may be the answer for riders who still want a day's competition but who have given up riding trials (in the normal sense) due to the physical effort of man-handling a big banger around 30 sections for several hours. If so I genuinely hope it keeps the big bike brigade going for a good few years yet. I have nothing against the big bikes by the way, my comments are purely in the context of newer riders coming through to keep the class going as the original set drop away. I've always fancied a trick Ariel and if I could choose a bike to ride in the Pre65 Scottish it would be one of those.

I understand what you are saying about some sections and the duration of an entire event, but this is what I was alluding to in my post. The gents that were the mainstay of this class are getting on and some can no longer cope with the physical effort of a complete trial on one of the big bangers. They are either stopping riding or switching to smaller, lighter bikes. I could be wrong onviously but I can't see significant numbers of riders replacing them. The interest in riding those bikes isn't there - from what I see travelling around, but I don't do YC or Red Rose events and haven't been to Bath or Golden Valley for a while and they are some of the bigger clubs, so can't comment on the bikes in use there. Regarding the Miller rounds, it's difficult to see how the easier route could be eased off any more without taking the challenge away for most of the riders on that route, as it has to cope with quite a range of bikes - unit, 2-stroke, Pre-unit, rigid and sidecar. The sections on that route are fine for the big bikes but their numbers have all but disappeared over the years. Other than the reason given above it is difficult to see why. There are some links below to some 60s trials, one or two of which may have been on here before. Some of the sections from these genuine 60s trials are harder than a lot of the easier route Miller sections. Looking at these bikes though, it is difficult to summon the enthusiasm to want to ride bikes of that standard now....

What is the reason for diminishing numbers of big Pre-units nowadays? Take the Miller series as an example. The easy route is ideal for Pre-unit springers in standard trim as the same route has to allow for rigids and there are a few rigids competing for the last ??? number of years. So you don't need a

Cheat bike is a term that doesn't really apply any longer to a Pre65 bike and hasn't for some time As the modifications became commonplace and accepted over the years, rules were introduced to allow and police them, some of which are plain ridiculous but we won't get into that. And so we now have rules that allow the following: Replica frames from modern tubing Replica hubs and yokes from billet machining Pre65 fork sliders with modern internals up to max 35mm diameter stanchions So you can't call bikes built around the above criteria 'cheat bikes'. It is how Pre65 has evolved as a class and they are within those rules, the modernising is allowed - there is very little scope left in which to cheat (or need to try) Unless you can call using European or Japanese hubs, a pair of Ossa or Yamaha (in line spindle, look the same as MP) forks instead of 'hiding' them in some Norton or suchlike sliders, European or Japanese yokes, cheating. Hard to see how though as cheating implies gaining advantage by breaking rules and none of those give any advantage over the accepted billet replacements for those components - other than a reduced cost.

SamYam is most likely the one that did the cutting and welding on the frames in Shirt's workshop

It's Allowed. As regards the big British bikes, what's changed? I can see they've altered the classes but there are still two routes, you can still ride a pre-unit on either and the best performance on a 2-stroke, unit and pre-unit at the end of the series will get an award, so where's the problem? I can see there is no dedicated pre-unit class in each event anymore but that doesn't prevent you getting out there for the enjoyment of riding your pre-units in a big single lap trial.

I spent ages looking at my frame and a standard one and this is what I could see (or thought I could see...) The rear tubes up to the rear loop are unaltered. The front tubes up to the seat are shortened somewhere and the seat rails are detached from the main tube that runs under the tank. The rear subframe is now completely free from the rest of the frame at this point. The subframe is then lifted up and tilted forward and reattached to the main frame tube. The way the rear tubes are attached to the rear of the main tube, just behind the area where the extension bracing from the toolbox ends, that whole area is different in appearance. That's how it appeared to me when I was trying to work it out. I found it facinating, wondering how they arrived at this solution. Having had one of each and ridden them back to back, I actually thought the Yam framed bike was the better version of the two and rode nicer. It was lighter on the front and more flickable. The Godden framed bike was front heavy.

The head angle wasn't altered on them - if it looks like it is it's probably an illusion. Only works bikes, if any, had altered steering. The side view pictures of each frame are very good for a comparison. You can see the difference at the rear of the frame but it is so difficult to work out how it was done - and how they actually arrived at that solution. The frame tubes from footrests up to the back loop aren't altered, only the forward facing ones to match the higher front engine mount. Clever stuff

The two bikes are like chalk and cheese really. The MH has much quicker steering with reduced angle and although I don't know measurements etc, the frame is very different from the white wonder. I don't know if fitting the banana swingarm would be of any benefit as I don't know if it is longer/shorter/same as the older one. It's not just the length of the arm, it's the pivot point also that may be different. Once you start it's a minefield. Rathmell had one on his white wonder works bike but it was obviously the start of the development of the next model and you don't know what else was altered. It would probably be cheaper to look out for an MH than it would have somebody try and modify yours. At the time they were new, the white wonders were a bit long compared to the earlier bikes and also to the other new bikes that were being developed. On today's classic club route sections though, or even a modern B or C route, I doubt that is now a hinderance, those sections are nowhere near as hard as the national or centre standard sections that the bike would have had to cope with back in its day. Honest opinion is to just leave it as it is, you've had the most benficial mod done in lowering the footrests, if you try to get it modified into an MH you could end up in no-man's land with it and a big bill. Edit: Ideal as it is for Miller rounds as well. Nothing in them it can't cope with.