anyone fancy supermono??

[OMEGAMAN]

 
I agree with steve's comment on starting, but if you have regular help, I think your best investment would be a set of rollers (with which you can start the bike up on your own driveway, or in the wet!), & a boon at the race meeting, (although there are always others in the mono paddock willing to let you use their's) Or, if your old & unfit like me, just sit on the bike & get your assistant to push!

[canolman]

Thanks lads, are rollers available to buy or are they a 'homebrew' job? I saw a half a Mini-Moto used at Angelsey once and thought I might give it a try.
The last thing I want is to be running up and down the paddock with 5 minutes to go!
It would be nice to fire her up on own, ie in my garage etc......powered rollers?.......hmmmm
I'll come up with something, I usually do!

[guest27]

If you are worried about the wrong way round wheel - I was on mine - the Aprillia 125 has a Rotax lump and thus the wheel has its drive on the right and brake on the left.

R

[OMEGAMAN]

Thanks lads, are rollers available to buy or are they a 'homebrew' job? I saw a half a Mini-Moto used at Angelsey once and thought I might give it a try.
The last thing I want is to be running up and down the paddock with 5 minutes to go!
It would be nice to fire her up on own, ie in my garage etc......powered rollers?.......hmmmm
I'll come up with something, I usually do!

In your garage???

Better have some bloody good earplugs handy!

[canolman]

When I first got the bike the wheels were KR1s which I swapped for '22 RGV. I've just been sorting through parts ready for Ebay and noticed that the homemade chain adjusters that were used originally (KR1s has a smaller wheel spindle) has the words 'wotsit & thingy racing' scratched on them. Does that ring any bells with anyone?
I know it's a long shot but I would really like to trace the builder
Thanks in advance

[canolman]

I still haven't traced the builder, I'm probably going to wait until it explodes and find out the engine spec. when I rebuild her! The previous owner on the IoM didn't ride her (that's 3 in total!) but he was sure she came from Wigan and raced at Three Sisters. I have now taken her out on track , a couple of sessions at Oulton Park, I took it very steady to start with but pushed a bit harder in the second session.........very very happy, pulls like a train and steers well, needs a little setting up but overall I'm impressed, according to the TrailTech Vapor rev counter I'm using which records your highest RPM I touched 9000 rpm!!!! didn't feel or sound over-revved though but I better be careful!
to all of you who have helped thanks a lot,
canolman

[canolman]

I've now got a little info on the motor,
560cc (not 604cc as advertised!!)
860 cam
34mm inlet valves
Gas-flowed head
I'm pleased overall but disappointed that she is a 560cc motor and not the 604cc, I reckon she makes about 50hp. I'm looking for more power!! The price of a big-bore kit is a bit steep as the casings have to be machined to fit a larger liner. I'm thinking of changing the 40mm Amal carb for something else, any suggestions?
I've raced her recently and was really pleased with the handling and the brakes are phenomenal!!
I'd put the power to weight ratio on par with my CBR400 race bike but the 'mono would out-brake and change direction quicker.
A problem I think I'm going to have is beating the 105db noise limit, the pipe is a 2"bore straight through, if I baffle it I lose power .....catch 22, has anyone got any tips?
thanks.

[guest27]

Hi There
I have a Mikuni 44mm (I think may be 42 with enough meat to become 44) that I picked up for my Rotax.  Being as hell will probably freeze over before I get anything sorted if you are interested you could possibly 'borrow' it.

It is not a VM after market jobbie but is from some bike as original kit, but I understand all the jets etc fit just the same.  If you like you may borrow it and see if you can get a manifold sorted for her, if she then jets up and you like the outcome we can discuss a price - she owes me about £50 I think - mind I might take the 40mm amal as a swap.  If you do not like her just send her back - with the new jetting - and she will be there or there abouts for me if I ever get around to fitting it.

Would save you forking out for a big bore Mikuni only to find the Amal is easier.

AS I said if you like... above is only a suggestion - open to others - but keep them clean!

R

[canolman]

Thanks Rog,
I'm in 'negotiations' at the moment and one of the debates we are having is whether to go bigger than 40mm, the arguement being that the inlet is 40mm so would a larger carb. bore actually create more power ...something to do with velocity speed? . We are going to do a bit more research and see what we can come up with . I'll give your big 'un ( ) a miss for now, thanks anyway,

 

[guest27]

It is an open offer - so bear it in mind.

I know there are lots of theories out there.. JR in his tuning books suggests that the carb should be
d^2/40=p where d is the carb diameter in mm and p is the power the engine makes.

If you are making 50 hp d = square root (50X40) = 44.7mm

He also suggests that there should be a taper from carb to valve so that the valve is approc 80% of the carb area

34mm = 907 X 2 = 1814 / 80 = 22.675 * 100 = 2267.5mm^2

2265.7 / pi = 721.76 *^-2 = 26.86 mm rad = 53.73mm dia

My maths may well be wrong and there are many many other factors - like midrange... but JRs calcs suggest that the valves are too big for the engine power or the carb is too small (40mm)

Mez porting (when he was alive) used to do a twin carb conversion for the Rotax so it could run 37.5 inlets and a pair of 38mm carbs.  He also did manifolds to hold 44mm Miks

You probably know all of this anyway but thought I would throw it into the pot.

Best of luck

R