I was told the diff between the 250 and 500 was they spent money on better hardening for the 500 and welched on the 250. Part number search would find out if my source was FOS, as he occasionally was.
I was told the diff between the 250 and 500 was they spent money on better hardening for the 500 and welched on the 250. Part number search would find out if my source was FOS, as he occasionally was.
Don't you look at my accountant.
He's the only one I've got.
I'd have been quite happy with 4 gears. They were bloody near square standard, and mine were stroked, torque at 4k was almost the same as 8k.
The first time I had trouble there was some wear involved, but teeth were also broken. The second I actually split in half. Like I said, I suspect the second at least was an aberation.
By the time the 500 came along they'd made quite a few changes. A mate had a 350K2 and while "nimble" wasn't a word that'd spring naturally to mind wrt mine, his required a lot more warning of impending corners. I only ever rode one 500, and I liked that better.
Go soothingly on the grease mud, as there lurks the skid demon
No idea about the relevance to "down under" markets, but I believe there's a lot of commonality in Rotax gearboxes and there used to be/are lots of different ratios available for the 125s and 250s including the karting clones, maybe?I
If they're not too wide, what about Yam twins - Banshee for off-road, couple of different road sets and TZ/Nova for the high end?
Grumph, did Britten use standard ratios? Think I remember you talked him out of the GSXR750 6 speed?
I thought it was slightly odd that the Tularis, Melly Blue Rage and Ian Cramp's Lionheart all used Duc boxes when the Ducati works riders were complaining about having no alternative ratios.
I suspect that anywhere in the world, you use what you can get...Yes, there are a lot of Yam twins here, gearbox karts, probably a lot of Rotax max - but they don't seem to get written off. JB's first iteration was the Denco built, Colin Lyster designed speedway engine which used an XS650 Yam box - again, just what Bob Densem could find at the local wreckers...Later versions used initially the GSX1100 box then I'm pretty sure all the "production" bikes went to the GSXR1100 box - bought new - and probably at full price too.
Homebuilt stuff in my experience anyway generally has no thought given to alternative gearbox ratios - you're too keen to see it run.....
At the end of the day I could just make the buggers but where do you draw the line? I can get a pull broach from out of India (for making splines real quick) at $800 NZD . Not a bad price I thought considering, but I would need a gear shaper as my hobb won't do teeth up to an edge. The Indian company I deal with has made all my gear hobb cutters and they are nice, concentric and hard wearing. For one off why bother, I can use Precision Gears in Rotorua to do my one off oddball stuff, they are not too bad price wise.
So you have an eBay search setup?
http://m.ebay.com/itm/YAMAHA-YZF250-...%257Ciid%253A6
Surely there are junkyards in the states littered with blown mx bikes that could post you 5 at a time. Get Husa on the search.
Don't you look at my accountant.
He's the only one I've got.
Guy down here specialises in vintage AJS stuff. Got a broach made in India for a spline which is used on them for pedals, brake lever arms, gearbox and engine components. Told me it cost him about $300NZ 6 years back. He's been selling new components ever since. Good business.
There's a lot of Ducati gearboxes and other engine parts on eBay here in the USA and the prices look quite reasonable. Since they are off of big twins they are sized for a 400-500cc 4T single torque spike.
Sorry, but Just butting in to change the subject for a minute!
Someone a few pages back mentioned a plastic material ("Blue Stuff) which can be softened in boiling water and "puttied" into or around an original pattern then used to make a rigid corebox (such as Flettner was doing way back, with Vinamold) - eg transfers etc. so I ordered some just for interest sake.
It has arrived and it seems about the same consistency as a soft school eraser when cool and firmer than your average silicon from a gun - so it's quite firm and appears to retain it's shape well after extraction.
It looks to me that it might work as well as "Vinamold" - probably cheaper too! but whether or not it can be heated to a pourable state without destroying it I'll have to find out - this in many cases, might not really be necessary anyway!
Fortunately I have found somewhere about three quarters of an hour away where I can carry out my foundry work (as opposed to just talking about it ) I will also have some help available and will not have to worry about neighbours. My neighbours here are all fine of course and I want to keep it that way! - starting up a foundry in cramped quarters like mine is not really the done thing!
BTW Neil I would like to see you doing a pour sometime as well, might help me resolve a few questions in my mind on how to go about it! - ie if I can ever manage to divorce myself from family duties!
Strokers Galore!
Got the slider engine running on the dyno again. Only problem was that it put out so much power that the quality $16 fishing scale/accurate load cell failed, the needle breaking off.
Nah, to tell the truth, at around 10k, the needle went into a frazzle and, like a pommy Smiths speedo, the needle gave up and found happiness lying horizontally at the bottom of the dial.
Irrespective though, the dyno water circuit is still not right, offering either no load or running into a brick wall.
"Success is the ability to go from one failure to another with no loss of enthusiasm.”
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