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#Post#: 6964--------------------------------------------------
Wet clutch and reduction, or CVT?
By: Long83 Date: May 28, 2022, 7:32 am
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Hi all, I've been having a look on eBay and found a Lifan 6.5hp
engine with 2:1 reduction and a wet clutch. It seems as though
its a centrifugal clutch but it actuates a 5 plate wet clutch
(if that makes any sense). I've had a look at the clutch spares,
and it's the same parts for the GX390 so should handle a stage 1
200 engine ok.
HTML https://www.ebay.co.uk/itm/363072916091?hash=item5488d50a7b:g:4OAAAOSw8NxdSreW
Does anyone have any experience with these? I'm tempted as it
may work out cheaper than using a CVT. Or does a CVT work better
because you can keep the engine at peak torque across a greater
spread of road speed?
Cheers
Philip
#Post#: 6967--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: ChrisS Date: May 28, 2022, 1:45 pm
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Hi Philip,
I am the only GB user of one of these currently, so you can see
that most people opt for the CVT! It has some advantages and
obviously some disadvantages which I'll try to capture:
Advantages - Engine/gearbox unit is more compact than engine/CVT
- Also the 2:1 reduction means you can use a much smaller
sprocket on the rear axle which again helps with a compact
install - Trouble free, none of the issues that you can have
with CVT belts etc
Disadvantages - As you say, you can't get into the power band as
readily and this is most apparent on a standing start and
exiting very low speed corners
I try to mitigate the low speed power differential by using a
selection of drive sprockets and I swap them according to the
circuit and conditions.
I would suggest if you want reliability and a neat compact
install go for the reduction box, if you want performance, go
for the CVT.
#Post#: 6970--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: Long83 Date: May 29, 2022, 1:10 pm
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Hi Chris,
Thanks for the info, and sharing your 1st hand experience.
Out of interest, do you know roughly what rpm the clutch kicks
in at?
Thanks again
#Post#: 6979--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: ChrisS Date: May 30, 2022, 4:51 am
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No I don't, I'm afraid
#Post#: 6980--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: RhysN Date: May 30, 2022, 7:40 am
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[quote author=Long83 link=topic=902.msg6970#msg6970
date=1653847845]
Hi Chris,
Thanks for the info, and sharing your 1st hand experience.
Out of interest, do you know roughly what rpm the clutch kicks
in at?
Thanks again
[/quote]
I used several of these on fairground rides I made. The clutch
is supposed to be biting about 1800 rpm.
#Post#: 6981--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: Adrian Date: May 30, 2022, 7:48 am
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That is a subject in its own right and I dont think you can get
anything to help other than a higher reving engine with more
torque at the 4000 rpm area.
You can cut the weight's in half (looking from the casing) and
fit a stronger spring in the clutch and that raises the rpm
before the clutch bites.
That what I have gone for and I have tuned the engine so that it
will rev to around 9000 rpm. Unfortunatley, that give more than
10hp so I have to moderate it. I can fir a limiter I supose so I
done get more than 10hp?
You need to knock-up a dyno to check it out. I am working on one
now and when its done (?) I'll take some photos and explain its
workings.
It will be portable and any cyclekart will fit so I could bring
it to a meeting????
#Post#: 6984--------------------------------------------------
Re: Wet clutch and reduction, or CVT?
By: Long83 Date: May 31, 2022, 2:59 am
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Thank you all for the extra info, I think I'll probably end up
going the CVT route.
I am very intrigued by the dyno build! Really looking forward to
hearing more about that when it's up and running.
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