Fitting a 60mm crank.

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jaymarriott
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Afternoon all,
I heard different opinons about fitting a 60mm crank.
Some say it will just fit in and others say you need to use a dremel in the casing so the crank fits and don't rub. :?
What is your say on this?
Cheers :)
cezeta
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depends on the crank, af one harry barlows one and mbd one goes streight in (have the af one welded) others have the big end protruding from the webs so they may rub.
Bilko
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PM Tuning crank goes straight in too with no modification needed
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Directionally dysfunctional since 1966
jaymarriott
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The crank I have is a Mec-eur one with a polished rod.

Cheers.
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corrado
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I'm about to find out with a 60 x 116 crank that I got from LTH. I'll dry build it and put masking tape inside the casing and turn the engine over carefully by hand so see if it leaves any marks on the masking tape.
Seems to differ from rod to rod as to whether the big end protrudes or not. Of the 60 mm cranks I have here the AF race crank big end doesn't protrude but the LTH, the MEC and the Tino cranks do protrude. I was told by a mate with a 60mm MEC that he said Martin at Chiselspeed reckons that you should channel the casing with all 60mm cranks, though I didn't hear that direct from Martin. Based on that info I dremeled my casing when I fitted a Tino 60mm crank in a Rapido 250, it was only a 10 minute job involving lots of scientific data (ie guess work), prob removed about half a mm around the track of the big end path.
jaymarriott
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Do you think the 60mm crank will be any good with the Imola kit then?
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corrado
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jaymarriott wrote:Do you think the 60mm crank will be any good with the Imola kit then?
You're in the same situation as I am. I'm building a 225 Mugello with LTH reed valve, Mikuni TM24, 60 x 116 crank and a TS1 piston to suit the long rod but inlet durations, degrees of this and that are a foreign language to me so I'll put it all together myself and get a grown up who understands port timings to tell me if it'll do what I want it to do and if not if he can alter the ports to make produce it's power where I want it, ie max bhp and max torque both below 6000 rpm so that it'll pull 4.4 gearing helped by an ADS3 touring exhaust.
Without putting it together and then doing those measurements you're not going to know but it will definitely alter your port timings, whether for good or bad I don't know.
The main objective is what do you want from the kit and what is your style of riding? An Imola kit would be considered a high revving kit and should in theory produce it's power (as it came from the factory) higher up the rev range than the Mugello but no doubt that both kits can be tuned to suit specific requirements. I think that gearing is the key and then build everything else around that. I loved my Imola before I made the gearing too tall and loved pushing it to 8000 rpm for an adrenelin buzz but that's not what many people want, they may think they do but will bottle out once you get anything over a genuine 65 mph [genuine not Lambretta speedo]. Infact half the people I know don't even like going on a motorway let along doing 80 in the outside lane. The Muggy I'm building is the complete opposite in that I want it to be able to sit on the M1 at 60mph at 5500 rpm for hours on end so it puts less stress on all the components and also does 70 mpg.

Anyway I'm outta here, the Sun's shining and I've got to put my scooter back together for Scarborough on Saturday.
jaymarriott
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Mmmm, I want something to pull me foreskin back with an adrenelin rush ;)
Hopefully it'll be sort soon.

Good luck with the rebuild and have a safe journey, and have a :fb: for me.
jaymarriott
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Sounds good,
I'm on of those who want to sit at 80mph in the fast lane of the motorway, but being 18 stone has put paid to that I guess, :oops:

The exhaust choices are a RS tuning clubman, though I need a downpipe making for the Imola barrel. The other choice is a sterling expansion.....
:freak:
cezeta
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ive got a rs ts1/imola downpipe. made by ralph and brand new. (had both made just in case)
pm me if you are interested
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