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#Post#: 9236--------------------------------------------------
CV Transmission Problem
By: Max Venturi Date: August 9, 2023, 9:30 am
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This afternoon the CV unit decided to fling itself apart. I've
found all the parts except one bob weight. There was no loud
bang so chances are it is in a flower bed. Either that or it has
flown over the fence!
Are these weights available separately and if not where is the
best place to go for transmission spares?
The problem seems to be the length of the bolt. I've run an M8
tap as far down the shaft as it will go and the optimum bolt
length is 60mm compared to the one fitted which is just 45mm.
Thanks in advance
#Post#: 9244--------------------------------------------------
Re: CV Transmission Problem
By: Andy Dunn Date: August 11, 2023, 2:04 am
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Hi Max,
Gemini karts sell various spares for comet CVTs ,just had a look
and they do the complete weight assembly on its own ,I've used
them and very helpful company
#Post#: 9245--------------------------------------------------
Re: CV Transmission Problem
By: Max Venturi Date: August 11, 2023, 3:12 am
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Thanks Andy. I spoke to Chris at GK yesterday as it happens and
yes, they do sell the weights separately. Comet 200344 Zinc
Weights are the ones I need but @ £26.70 plus p&p & VAT I'll
wait until after the weekend and spend some more time trying to
find the missing one.
The design of this CVT unit is a bit disappointing. Assuming the
OEM bolt was the one fitted it is too short and there should at
least be a locking tab washer. I've fitted a longer bolt and
made a locking washer. The bolt will need a hole drilled in the
head to fit a security wire.
Of course the biggest design failure is on the motor itself, ie
there should be a left-hand thread on the shaft.
For any one who's CVT unit regularly shakes itself loose I'd
suggest you check the length of the bolt and fit a locking
washer.
#Post#: 9246--------------------------------------------------
Re: CV Transmission Problem
By: Jimr1999 Date: August 11, 2023, 4:26 am
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Just thinking about the thread hand Max...
"Of course the biggest design failure is on the motor itself, ie
there should be a left-hand thread on the shaft."
The motor rotates anticlockwise as viewed from the shaft, which
is the same direction as a nearside wheel (UK). And spinners ,
nearside U.K are set to a clockwise thread? Does that indicate
that the correct thread for the shaft should be clockwise?
JimR
#Post#: 9247--------------------------------------------------
Re: CV Transmission Problem
By: Max Venturi Date: August 11, 2023, 5:15 am
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Leftie loosie -righty thighty ;D
Picture shows a simple tab washer for use with lock wire. Just
drill a hole in the bolt head and loop a lock-wire through the
that hole and the hole in the tab washer. (NB. this isn't the
bolt I'm using, this one is just an example - Allen bolts are
easier to drill for this job).
Or even easier would be to make a tab washer out of aluminium
and fold an edge over the hex head on the bolt. The washer
doesn't even need to be round!
So the question is; given that it is this simple to correct a
design fault why don't the CVT units come with a tab washer? (&
a long bolt! :)).
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