ty 250 mono aftermarket parts

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Jon V8
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Re: ty 250 mono aftermarket parts

Postby Jon V8 » Fri Jan 27, 2012 8:58 am

As I said,if you want to change anything about Bath Classic trials - join the club,come to the meetings and make the suggestions there.



FM350
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Re: ty 250 mono aftermarket parts

Postby FM350 » Fri Jan 27, 2012 7:56 pm

If you are happy to exclude rigids and sidecars but cater for moderns then thats a decision for your club, who very possibly get more riders on moderns than they would on rigids or sidecars if a 3 route format was adopted.



Jon V8
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Re: ty 250 mono aftermarket parts

Postby Jon V8 » Fri Jan 27, 2012 9:37 pm

We certainly do NOT exclude rigid bikes,far from it and they are ridden in both A and B routes. I have done all I can to encourage them.We have found that two routes are perfectly adequate,none of the B riders have ever asked for a third route - many feel that two route make riding far clearer in the sections by not having a myriad of multi - coloured flags to negotiate.
As for sidecars,nobody has ever asked me if we accept them,I have never seen one at a Bath trial before I took over either.Nor have I ever seen one at either of the Somerton clubs,the only outfits I see are at Golden Valley where they ocassionally have up to about 3.
This is my last post on this thread as it is nothing to do with TY mono's and I feel I have explained in plenty of detail how our club works and the way to change it if it does not suit you.



FM350
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Re: ty 250 mono aftermarket parts

Postby FM350 » Sat Jan 28, 2012 8:13 am

Thats fine then Jon, but you must have some pretty handy riders in your neck of the woods, if they can cope with sections laid out for moderns and TS on a rigid!



Ferretflasher
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Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Tue Jan 31, 2012 8:05 am

Quite a few changes to the Normandale rider line-up this year .......... Chris Kock now on 125 Scorpa Air Cooled Mono (not the 250 Cotswold now possibly due to outside pressures??..... anyone know??) and Pete Roscoe on Fantic, not the GG he's tricked up over the years. Anyway shall ask Chris if Cotswold finished with or if its just on major rebuild as I vaguely remember he said something about new air box needed and other works. There is also a baby 200 cc Cotswold entered, have seen it before and it rides very well !!
First Normandale event is Colchester round and its a bloomin good ride around, nice moderate sections in superb countryside. Generally OK sections with a just a few evil ones for good measure. Plenty of interest in A class with some 21 riders ......... and a D Thorpe at #5 !!! ...right at the front ..... bet he dont start on time !!! :lol:



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Re: ty 250 mono aftermarket parts

Postby FM350 » Tue Jan 31, 2012 7:03 pm

Not sure why there would be any "outside" pressures on Chris not to ride his twin-shock mono again this year, as it conforms 100% to ACU rules? Pretty much every UK club running classic events allows Scottish rules "P65" twin-shocks to run in the P65 class, so maybe its time to start welcoming converted mono-shock bikes, which will provide a much cheaper and easier way for anyone to build a relatively competitive twin-shock bike? If on the other hand there is strong feeling about originality of machines, then maybe the Scottish rules twin-shocks need to be ridden in the twin-shock class, or better still in a specials class which would be open to anything with air-cooled motor, 2 shocks, and drum brakes?



Ferretflasher
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Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Wed Feb 01, 2012 4:38 am

Right back to thread, fitted IT crank into TY Mono. 2mm shims either side have centred crank nicely and it all fits lovely ! As can be seen there is now a lot of empty space in there that would originally have been TY tractor crank. This has the effect of increasing volume and reducing scavenge pressure within the crankcase. Time will tell if this is detrimental to the performance as it basically undoes the benefit of reduced inlet length, etc.
Shall order a 70mm Wiseco YX MX piston from Birks and this should bring displacement back to 250. These have the large crescent cutout at back so again its a another unknown added to the pot!!
Attachments
IMG_3668.JPG
Large empty space in crankcase compared to standard tractor flywheel



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Re: ty 250 mono aftermarket parts

Postby FM350 » Wed Feb 01, 2012 6:36 am

I would think the fact you have probably reduced crankcase compression by around 30%, that this is likely to have quite a noticeable effect on performance. But I guess if its something that was carried out on the works bikes back in the day, that its got to be something thats well worth doing.



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Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Thu Feb 02, 2012 7:11 am

Spoken to a local scooter racing guy other day and he thinks that because I have increased the volume of fuel/air within the crank case then there is more fuel/air to be scavenged into the transfer ports and hence more into cylinder. With the standard flywheel, there was not much free space left in there, most of the volume was contained in the 2 halves where the rod is located, it really is a snug fit in there as standard.
Its either going to go 1-of-2 ways .... it will be either totally rubbish or will rev like a good 'un !! Time will tell !!!
Bought a clutch of eBay other day and it contains dimpled steel plates .... never seen a TY with dimpled plates before ...... its a trick often used with Mont 315R plates as these are same as CR250 'Sureflex' MX clutches. Dimples hold oil and prevent drag when faffing with gears etc stops the steel plates sticking to the friction plates.



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Re: ty 250 mono aftermarket parts

Postby FM350 » Thu Feb 02, 2012 12:35 pm

So reducing crankcase compression is not a works mod you have on your ex works MA motor then?




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