turbofurball

Now that's a nice piece of garage engineering!

Ooh, just remembered another change which might be useful to others who are treading a similar route - I trimmed the stator cover so that the front sprocket isn't completely covered. Any sticky type mud gets jammed up around the sprocket and this just lets it come out easier (though it's not been put to the test, yet)

You need to remove the end cap to change the exhaust packing regularly anyway

Yeah, all the changes add up to it being a completely different bike

Maybe it's because mine is the single box version then, lol

Could you tell that to my TY, please? Because with the WES it's far, far, louder

Well, it's been about a year, and this is "Phase 2" ... Changes since Phase 1 are Magicals progressive fork springs, forks also stripped and painted and had fresh oil too, carb ultrasonically cleaned and rebuilt with new o-rings etc, gone up one size on both jets, new larger ally air box which was then changed a little to allow more airflow, fibre reed valves, a Shedworks tank-seat unit (it's a Montesa style, with a rough ally tank under a shiny fibreglass cover), and the front sprocket has gone up from 12 tooth to 14. I've switched from 10w40 to ATF in the gearbox, too, though that doesn't appear to have helped with the sticky clutch yet ... maybe I need to change it again to wash out the last of the old oil (I changed it while the bike was cold) The net result of all this - it's a smidge lighter (though I've lost a lot of weight this year, which has made a bigger improvement!), the gearing up hasn't overtaken the performance improvement from the airbox, and it pulls better at the low end ... however I am finding I border on stalling it when I want to go super slow in 2nd, so I might drop to a 13 tooth if I have trouble adapting how I ride. Anyway, it's certainly moving in a more sprightly manner now! I still haven't sorted the side stand, and the next major change will be rebuilt wheels. I'll be trying the next size up idle jet too, just in case there's more bottom end to be had.

If that 2nd pic is of a "Mk4" was there ever a Mk5?

Is it one of these? When you say wood screw, do you mean a self-tapper? If so it'll be fine, I've had stainless self-tappers in exhausts before and no problems have occured! The Spanish Fly ones are HERE, and looks nicely finished

Not at all, but any simple method (eg. checking the V5 or whatever) will inevitably see people curcumventing rules using any trick they can. Perhaps the only way around it would be silouhette checking, kinda like they used to do for NASCAR - namely, having a guide to what a bike of a certain age should look like and having someone judge it - though then you start getting competitive types complaining about judge's decisions and so forth.

For anyone searching in the future, the seal is 26x38x5 single sided, and the collar is 20x26x11.3 (Yamaha p/n: 90387-202A0)

Well, that's where two bikes come in - the TY is headed towards riding like a modern bike with all the mods (hopping on the back wheel notwithstanding, I'll never be able to do that), and the Cota is bone stock and about as heavy as I can handle, lol But I'm not competitive, just there to enjoy riding, so like you I have no horse in this race really!

I got new yokes which lost the tiller effect, steepened the steering angle, put the handlebars in a good place for a taller rider (I'm 5'10, 178cm), and allowed me to use modern fatbars that look similar to the original ones

Non-period correct frame mods? Steering angles? The problem then occurs that checking the bikes becomes a minefield, people would need to keep a table of stock period bike specs and be measuring stuff

I wash my stuff in Tekwash and then Nikwax, no problems so far (including riding on a motorway at 80 for two hours of solid rain and hail, lol)

Not really, since I got them for a TY175 The chap at Rock Shocks will probably know though (I got a non-standard length due to frame mods)

It's only fair to give you a heads up - I had a massive problem with Rock Shocks. When I fitted them they were so good that I suddenly became aware of how crap my fork springs were, so I had to go and get a set of fresh progressive springs for them too! Seriously, they're about as good as you can get, and I'm happy I stretched to the extra cost over the Betors that I was looking at.

I've found my (army surplus) sealskinz work great, but I don't find them comfortable. Next wet outing I might experiment with thin socks under them and see if that helps

Some of the last twinshocks had seats less thick than that!

The good thing about a sweat wicking base layer is it can be a top layer in the summer, too I've got a couple of nice t-shirt shaped workout tops from Tescos that are ideal, and I got a running top designed for Muslim ladies for when I need to have my arms covered in summer competitions

Indeed, can't use any place for anything without it being insured etc. A local industrial park now has security guards to make sure nobody learns to drive there on the weekends, just finding a quiet spot is nigh on impossible

Army surplus goretex top and troosers for me - cheap and highly effective! Works nicely as an extra layer when in the dry, you won't find anything more waterproof, the trousers go on over boots, and they pack away into a small package. Also works well as an emergency set of waterproofs for road bikes

Plugs don't degrade, but it's a good ideal to get the contacts nice and clean - you can check the spark while it's out by putting the cap on, holding it's body to an earth point (eg. part of the engine without paint) and kicking the engine over

Is that why in the French competitions the bikes have lights fitted (?)

Note that on Montesas if you pull the clutch in it disconnects the kickstart ... The 248 is a cracking bike - I wish I could find some nice trials bikes in sheds, lol