Is this a VFR750 rear axle in a VFR400?

[StrayAlien]

Hi Fifer5,

Isn't life funny. I just arrived home last night from two days at the Phillip Island Circuit - the first PI outing with the 5" rim on it and I get email from this forum about your message. Nice one!

I am pretty sure I bought it from the fellow who bought it from you (in 2010) - I bought it as a spare, but ended up selling it on - but I kept the wheels and the axle after having read that the 160/165 slicks available these days are generally made for a 5.5" rim.

Actually, the local Bridgestone slick man here in Melbourne confirmed that a few days ago saying their 165 is a 250 GP tyre meant for a 5.5" rim.

So, I used their 165 ycy compound these last two days on the 5" rim and it was pretty good despite the extra 1.5 or so kg of weight. Stu Winton of SW Racing was the suspension tech for the two days and he said he thought profile looked fine on the 5" ... but I am temped to try the 165 on the 5.5 rim.

It is a shame you can't recall the exact mod to the axle as this forum is a great place to keep all that kind of knowledge for suture riders and racers.

You pics look like these:

http://www.bikersoracle.com/vfr/forum/s ... p?t=110929

Is that you or possibly a previous owner?

[Fifer5]

Life sure is funny, and the racing life is its own little world. I can't remember the guy's name I sold it to...Fred maybe?? he was a big Ducati nut, president of the local club or the like and didn't want to bend any of his Dukes so grabbed this off me. I had bought it from Peter Clements of Promecha - so the thing had pretty good suspension through it as you' d expect. For me it's not a case of being able to recall what was done to the hub, as I was never aware in the first place how they had done it! I only had a few snippets of general info on it. I bought the bike as a second ride to get more value and track time per entry fee, but found running two bikes a bit too much like hard work! Plus the 400's down here in Vic are pretty serious so if I wanted to be more competitive I had to commit to more time and money into developing the bike a bit - as it happened I was more interested in running my P6 750 so concentrated on that instead. I think I raced the 400 at 4 race meets and did one track day on it. That was it. Funnily enough I rode one again recently, a mate of mine has one and loves it (more than his RC30!!), we raced in the PCRA 1 hour on it last year, pic below.

That is my thread on the VFRclub forum yes, and its interesting to see you going through the similar exercise of establishing exactly what can be run on what rims - most people have a tendency to over tyre. I have run that 165 Brdigestone on 4.5, 4.75, 5 and 5.5 rims! By way of comparison if you look at the Dunlop equivalent 165 I think they recommend 5.25 as the right rim size...its all close enough. Nice to see someone else who weighs tyres! I've noticed significant differences in tyre weights as well, especially important for unsprung / centrifugal / overall weight. What tyre was the 165 1.5kg heavier than, did you mean the 155 x 18 slick??? The race photo of my old 400 is with a 165 on the 5.5 and it was fine. I think it fitted the 5" a little better but not much in it.

[StrayAlien]

Heya, yep. I bought it from the fellow you sold it to.

Re the Promecha thing. That is interesting .. because no one I know could identify what the rear shock was! I am guessing Peter whipped up something special. I never actually rode the bike, but like you, got it as a second bike then changed my mind. The fellow I sold it to loved it. He sms'd me a very happy message a month later saying he had just beat his PB at Broadford by 2 seconds on it. Chuffed he was.

Re the 1.5kg, that is just the larger rims over the stock rim. The EOM 4.5" is pretty light.

I think it is really cool that these bikes have lives of their own. Like, I was in Tassie a few months ago with the old (93) Ducati Superlight and a guy came over to see it and was very excited - he rode the exact bike on the day it was bought in South Australia in 1993 when his mate bought it over to his to show off. Cool eh, he bought me a beer. :-)

Well, thanks for popping up and for the advice. I'll likely give the 5.5" rim a go in the coming months. The 5" felt great. Oh, the clear coat on it had deteriorated badly so all that lovely shiny stuff took some elbow grease to get back. Here she is:

[Fifer5]

No worries, if I see you round the traps I'll come and say hello. I have a ZXR750 and RS250 which I'll do the occasional race meet on one or the other, later in the year.

[kostritzer]

Interesting conversation guys. I've just about finished swapping over a Duc 5.5" rear on my NC30 and I'm planning to run the Bridgestone 165 slick on it. I measured the overall circumference of the tire on both the original 4.5" wheel and the 5.5" Duc wheel and they're almost identical. According to the Bridgestone tire specs, the 165 is ideally supposed to be mounted on a 5.5" rim(though they say a 5.0-5.5 is ok). The tire is significantly less pinched on the 5.5, so it should help with edge grip. With the 165 on the 4.5 it's almost impossible to use the last few mm's of the tire edge!

[hrc rr]

ha seen this bike on another forum i'm on, that undertail exhaust is a dead give away

http://cbr250.com/forums/project-bikes/ ... build.html

[StrayAlien]

He heh. Nice one. I do love it when bikes have a life of their own. Personally, with such fine things I think we are merely custodians for the next owner. Our responsibility is to keep them in good order and help keep them going. Great to see this owner getting into it. :-)