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Top Speed

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Jack:
Hi all, seems my bike is not performing as well as it should, can someone please tell me what top speed could be expected from an F1 engine in a normal state of tune. Mine struggles to reach 80 mph and I was wondering what would be a realistic figure to expect.

Voxonda:
Jack wrote:

--- Quote ---Hi all, seems my bike is not performing as well as it should, can someone please tell me what top speed could be expected from an F1 engine in a normal state of tune. Mine struggles to reach 80 mph and I was wondering what would be a realistic figure to expect.
--- End quote ---


Hey Jack,
A normal good F1 did reach 120mph, or at least should have. But a 30 odd years engine, like it's drivers, won't be so fast anymore. But should still be able to pull 100-110 'no problem'. If it does not it need some handywork.

Cheers from Holland.

Jack:
Many thanks for that, looks like I need to do some more tinkering.;)

JonnyB:
beforeI had my carbs cleaned and balanced I was geting similar performance, I can get to just over a ton now, but GOD it's hairy, it's not like riding a modern superbike where it's a smooth ride all the way up.
Up to 70/80 it's fine after that It shakes, rattles and is very un happy.

Jack:
I rode the bike for the first time when I took it for it's test, which involved a ride down the A1.  It rides fine up to 65-70 mph but then just seems to fizzle out.  I must admit that the old bike was not filling me with the desire to push it much harder anyway, it was starting to feel decidedly vague in the handling department and I'm sure that from 70 mph the braking distance could be measured in minutes not meters ( and that is despite having three discs ).

I was planning to sort the carbs with a good clean out and then new floats and float valves, aswell as new main and idle jets. The ignition is of the points type but is all brand new, as are the spark plugs.

I'm pretty sure though that it is running far to rich - it will start from cold with no choke!!! ( If I put the choke on at all it promptly floods ). I have the mixture screws set at 1 1/4 turns out but it doesn't seem to make much difference what I set them at to to be honest.  The chokes themselves are all operating as they should as are the slides, so all in all the carbs are the prime suspects.

Even after taking into account the handling and brakes and any number of other little quirks that the bike displays, it still puts a smile on my face, and I did notice that the sport bike brigade took much more intrest in my old bike than I did in their shiney new machines. To that end I just want to try to get it running as good as I can.

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