Top speed

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lccpmj
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Top speed

Post by lccpmj » 05 Nov 2010, 15:22

Hi Everyone, is anyone running 14/45 gearing on a standardish bike. If so, what sort of top speed do you get. My Mk3 does about 75- 80ish, so don't know if it's limited by the gearing or not revving out properly. Cheers.

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Re: Top speed

Post by fallenmikethebike » 05 Nov 2010, 18:15

14/42 is standard, so it should rev out OK.
I would guess that your pretty much at maximum velocity for the gearing quoted.
I have never run my MK3 flat out so I'm unable co-berate your figures, though, 65 MPH does come up very quickly and easily, with what feels to be loads left on tap.
Mike
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knackeredMk1
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Re: Top speed

Post by knackeredMk1 » 05 Nov 2010, 18:38

Top speed for a good condition CRM is ~ 100mph with the correct gearing for speed. Why anyone should want to do it more than once is beyond me as just holding on is quite difficult and you sacrifice a lot of acceleration :!: .

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eddie666
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Re: Top speed

Post by eddie666 » 06 Nov 2010, 00:32

i have a mk2 with 14/48 sprokets and it will still do 90+ as standard,
make sure your carb is set up right with the right jets and a clean air filter , if some one has drilled holes in the air box it will weaken the fuel mix,

if you are getting ready for new rings you will lose power also make sure the power valve is working as it should,

if the bike pulles fast and strong through all the gears and the speedo sayes 80 odd then the speedo might be out, tyers can make a diffrence to the reading, higher profile tyres ( big knobelys ) than standard will make the spedo slower than your speed,

bigger wheel size = spedo will be less than atual speed
smaller wheel size = spedo will be showing more than atual speed

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lccpmj
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Re: Top speed

Post by lccpmj » 08 Nov 2010, 11:17

Cheers Guys,
The previous owner had drilled the airbox, so I've taped these up. Also cleaned the carb and checked the jets and needle posistion all standard. The powervalve's working as it should and the air filter's been cleaned. The power just seems to tail off after 3/4 throttle. Comparing it to a previous MK2 I had, it doesn't seem as quick. The mixture seems about right, judging by the plug - nice light brown colour. Maybe I'll try the standard gearing first before whipping the barrel off and checking the rings.

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knackeredMk1
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Re: Top speed

Post by knackeredMk1 » 08 Nov 2010, 11:21

Knobbly tyres and condition of the chain and sprockets will considerably effect the top speed you can get.

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Re: Top speed

Post by john7780 » 08 Nov 2010, 12:01

hes right about the tyres, ive got knobblys on my mk2 and ive found you lose a lot of traction because at any one point the tyres arent sitting fully on the road surface which causes the tyres to skip the faster you go thus losing even more traction, i would advise looking at your rings, its not a big job and can easily be done within 3 hours, my mk2 pulls all the way up to 70mph i havent tried to go any faster for 2 reasons though, 1 i ran out of road and 2 the tyres cause a lot of unstability, not in a severe way where you wobble from side to side but where you can feel them skipping, also has your end can and down pipe had a good clean or flush out? this can cause a slight loss of power too


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