The other day my missus had a near miss on our series 1 when somke t**t slammed his brakes on in front of her. She had to make an emergency stop and in doing so the throttle got stuck on andf the only way she could kill the engine was to let the clutch out whilst in gear at full revs! Obvioulsy the scooter lerched forward and p but came to a stop without her dropping it.
Afterwards we couldn't get it started and I noticed the kickstart was really stiff and there was a grinding noise coming from the flywheel side. I stripped it down and found that the flywheel had had one if the ignition coil faces come loose and it was catching on the stator. Checked the crank and there was no play in it but it didn't seem to be running true. I think it's twisted on the pin which has knocked it out of line and this is what has made the flywheel run out of true and catch on the stator? Might seem really obvious but have included a short clip and also a pic of the webs to get another opinion before I get another crank? Cheers.
Twisted crank?
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deff twisted ive got a ts1 in bits at the mo exactly the same thing ,put a straight edge across the crank webs at 12 oclock 3 oclock 6 and 9 that will show you how far out it is ,easy to wack back in to line then poss weld the pin
the cut outs dont always line up perfectly so dont let that throw you out...although your symptoms sound like it has twisted.
a straight edge could be used if its well out but ideally in should go on vee blocks or a crank jig and a DIAL INDICATOR used to tell you how much the run out is
a straight edge could be used if its well out but ideally in should go on vee blocks or a crank jig and a DIAL INDICATOR used to tell you how much the run out is
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That looks twisted but the only way to know for sure is to put it up on some centers and run a dial indicator to see how far out it is. I don't know about you but I can't see if a crank is .001" out with out some special tools. Only once it's trued up then can you have it welded.
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Is it true what I've been told by one reputable dealer? That being that if you weld a crank[either a new one or one that's been twisted] when the welding is cooling off,that this will naturally cause the crank to twist out of line.I would of though welding would securely fix the pin and properly,but have been told never to have one welded .If it want's securing ,then only use Loctite on the pin when assembling was their answer and theory. What's anybody elses opinion?
- scooterslag
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Just pull it out and send to someone like Al Diablo, he's done a couple of my cranks in the past and is a sound fella indeed. If nothing else, its piece of mind and he can sort out any problems while its there.
The mack daddy on the left!
- scooterslag
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I'm sure people like Taffspeed, MB's etc have welded their cranks in the pastspeedy wrote:Is it true what I've been told by one reputable dealer? That being that if you weld a crank[either a new one or one that's been twisted] when the welding is cooling off,that this will naturally cause the crank to twist out of line.I would of though welding would securely fix the pin and properly,but have been told never to have one welded .If it want's securing ,then only use Loctite on the pin when assembling was their answer and theory. What's anybody elses opinion?
The mack daddy on the left!
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If the welder has enough experience then they can predict how the crank will move when and where it's welded. It's one of those experience things you pay extra for.speedy wrote:Is it true what I've been told by one reputable dealer? That being that if you weld a crank[either a new one or one that's been twisted] when the welding is cooling off,that this will naturally cause the crank to twist out of line.I would of though welding would securely fix the pin and properly,but have been told never to have one welded .If it want's securing ,then only use Loctite on the pin when assembling was their answer and theory. What's anybody elses opinion?
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Sorry for the thread drift,but it's answered some of my questions.My own thoughts were to have em welded,but when someone puts a slight doubt in my mind[especially someone reputable],I tend to get a tad paranoid for want of a better word.Cheers folks.Speedy.