What is the smallest (specifically lightest) engine that will accept a torque converter? The 30 series torque converters all say 2-7hp or 3-8hp and have 3/4" bores, but all the 2, 2.5, and 3hp engines I find are 5/8" shaft. There are adapter sleeves and keys to adapt a 5/8" keyed shaft to a 3/4" keyed bore, but they won't work because all the torque converters I find have fixed keys in the bore that are machined as one piece instead of a key groove. I am thinking about a small 4" wheel mini to trail ride with, and torque converters are so much nicer than centrifugal clutches when trail riding at slower speeds, up hills, etc.....
Smallest engine with 3/4" shaft?
- Thread starter wardog
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anickode
Active member
I believe the 20 series is available for a 5/8" shaft...
A 5/8" driver? I have only found 5/8" driven pulleys..... All the drivers I have found are for 3/4" or 1" engine output shafts.
Texan
Senor Member
I have a 3hp Briggs flathead with a 3/4" shaft.
ezcome-ezgo
G'me sumthin to write on
bob58o
SuckSqueezeBangBlow
If the integrated key is half of a standard 3/16 x 3/16 key then it is 0.09375" deep.
The sleeve will be 0.0625" thick.
So it will extend 0.031" into the crank keyway. Is that enough? ... A normal key catches 3x as much of the crank.
I'll measure the key if I get a chance, not sure how deep it really is.
http://armstrongmetalcrafts.com/Reference/KeywayDimensions.aspx
The sleeve will be 0.0625" thick.
So it will extend 0.031" into the crank keyway. Is that enough? ... A normal key catches 3x as much of the crank.
I'll measure the key if I get a chance, not sure how deep it really is.
http://armstrongmetalcrafts.com/Reference/KeywayDimensions.aspx
Honda GX120 surely comes (alongside some other available options) with a 3/4" shaft.
(Q-type)
3.5hp net power (2.8hp const. rating)
I bet it's clones do as well ...
(confirmed.. Lifan LF160F-AQ has a 3/4" keyed shaft.. claims 4hp though)
'sid
(Q-type)
3.5hp net power (2.8hp const. rating)
I bet it's clones do as well ...
(confirmed.. Lifan LF160F-AQ has a 3/4" keyed shaft.. claims 4hp though)
'sid
bob58o
SuckSqueezeBangBlow
I don't comprehend this question.
79cc 3HP 22lbs
212cc 6.5HP 37.5lbs
Driver 150lbs
Roller 50lbs???
6.5HP 237.5 lbs 0.027 HP/lb
3HP 222 lbs 0.013 HP/lb
The engine may be lighter, but You'll spend more money, and still end up with less than half power to weight ratio.
Just sayin.... If the bigger engine fits.... Run it.
I personally don't think that is enough. There is a youtube vid of a guy plug welding a sleeve on so the key can butt up against it without the sleeve spinning on the shaft, but I don't really like that solution.
---------- Post added at 09:06 PM ---------- Previous post was at 08:51 PM ----------
I saw those when searching, but from the info I have found it seems they weigh almost as much as a 6.5.
I don't comprehend this question.
79cc 3HP 22lbs
212cc 6.5HP 37.5lbs
Driver 150lbs
Roller 50lbs???
6.5HP 237.5 lbs 0.027 HP/lb
3HP 222 lbs 0.013 HP/lb
The engine may be lighter, but You'll spend more money, and still end up with less than half power to weight ratio.
Just sayin.... If the bigger engine fits.... Run it.
Yea, the more I learn the more apparent it is that there is a reason everyone uses 6.5's. It is suprising how relatively big a 120cc or even 79cc engine is compared to a 212cc.
The 6.5 with a comet tav on my 3x3 performs great, but it is pretty big and heavy, or at least bigger and heavier than I want and especially wide. I am willing to sacrifice some top speed for lightweight and compact. Do you think a 120cc 4hp lifan with a tc will haul a 200 pounder up a steep trail and still have enough gear to make 20mph?
it's actually NOT that surprising, the 80cc is very little volume
(200cc is a coffee mug, 80cc.. two mokka cups roughly)
So it's fairly obvious that combustion volume
does not account for the weight of an engine really
(I mean 16kg does not come from a mug worth of empty space, right
)
So an engine half that combustion volume is not going to be just half that weight of course.
it's the "beefiness of parts" that require mass..
crank, conrod, head, case etc...
Small engines can be found elsewhere though (think 50cc mopeds and such)
even gas powered bike engines and whatnot;
3hp not a problem.. but that's unlikely what you'd want to use
So yeah... if it's not about fitting it inside a small frame, then go for the 6.5hp
even if you only need 4hp.. it's nice to run an engine far from it's limits
and it's even nicer to have an extra pack of oomph just in case that hill suddenly decides to steepen it's incline
'sid
(200cc is a coffee mug, 80cc.. two mokka cups roughly)
So it's fairly obvious that combustion volume
does not account for the weight of an engine really
(I mean 16kg does not come from a mug worth of empty space, right
)So an engine half that combustion volume is not going to be just half that weight of course.
it's the "beefiness of parts" that require mass..
crank, conrod, head, case etc...
Small engines can be found elsewhere though (think 50cc mopeds and such)
even gas powered bike engines and whatnot;
3hp not a problem.. but that's unlikely what you'd want to use
So yeah... if it's not about fitting it inside a small frame, then go for the 6.5hp
even if you only need 4hp.. it's nice to run an engine far from it's limits
and it's even nicer to have an extra pack of oomph just in case that hill suddenly decides to steepen it's incline
'sid
bob58o
SuckSqueezeBangBlow
Small two stroke engine running two jack shafts... One for Driver Unit. One for Driven. You seem to like complex drive systems so you might be able to figure something out. Slow down the two stroke RPMs to 4 stroke speeds so it will work with a CVT. 2 burns per cycle instead of 1 should up the power and keep the size down????
Those 80cc two stroke bicycle engines seem pretty small???
Those 80cc two stroke bicycle engines seem pretty small???
Tpdingo
Member
Arent those like 3/8 shaft?
bob58o
SuckSqueezeBangBlow
They might be, I have no idea. But the point of my post was that if you have two jackshafts, then shaft size becomes trivial.
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