Rev limit

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itsid

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that's quite a bit..
but yeah, a good overview helps a long way.
everything from the throttle pedal to the rear wheel could be the cause.

But let's not be too greedy .. I'd say:
1) Throttle connection on the engine showing most of the engine's left side
2) a full view of the TC so that we can see the state of the sheaves and belt (ideally with a legible belt marking)
3) Jackshaft, chain and sprockets,
4) a good glimpse of the rear axle and wheels (helps to see sprocket alignment mostly)
and maybe as a bonus for now..
5) throttle pedal and the way the throttle cable is attached to it (maybe we see a throttle limiting factor there)

And we might ask for details later on
like butterfly on the carb or the cam and buttons of the driven pulley maybe even the inside of the driver pulley... such things
So if you have enough time and daylight.. you could already take those pics just to speed things up ;)

'sid
 

950speed

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Here is some pictures. I would remove the tank, but still don’t have time. Let me know what other pictures I need to put up, what would help
 

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950speed

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It can’t be the throttle cable, ive used garage door grease and shot it down the line every so often to keep it smooth. Also there’s nothing that prevents it from opening up all the way. I don’t know if I’m unclear, but top speed is fine, it’s the acceleration part that is the problem. It starts accelerating but then quickly gets bogged down, or sound like the govoner pulls back on throttle.

If anyone saw an earlier post of mine using the shift light idea maybe say your opinion on it? It could work, if not I may just remove the govoner and add a tachometer.
 

itsid

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AWESOME!!

Soo.. belt 669 9a01 is a symmetric V belt made for Gy6 engines..

it has ZERO compatibility with a series30 Torque Converter belt.
what you need is this:
https://www.gokartsupply.com/5959belt.htm

AND NOTHING BUT THIS.. I know some label the 203589A as 5959.. but they're different as well, so be careful.

I know it's an expensive belt, but allow me to explain the reason for why it matters!

A GOOD (__extremely__ good) Torque converter Setup costs you about 20% of power,
so only 5.5 of your seven horses ever reach the driven pulley, no matter what.
This isn't much of a problem for the most part since the gear benefit it provides makes up for it in acceleration as well as top speed (strangely enough)
And that is, if the belt is in perfect condition!

In non ideal condition the belt simply doesn't make enough contcact with the sheaves
and thus can transmitt even less power
(V belts for example tilt and can never make good contact with both sheaves,
even if they were [they are NOT] as high and beefy as a proper TC belt)

So you loose a lot of power to that belt.. (I'd say upwards of 40% maybe 50% or such?)
soo essentially you are trying to power that kart with nothng but a 4 horse engine..
and for that the gear ratio is too tall.

So yeah, that is the very first thing you need to fix in order to make your kart move the best way possible.

Unfortunately, I can't see the butterfly and cable retention well enough in your pics,
So I still cannot rule out the throttle cable
I don't mean how good it runs in it's sleeve but if the pedal and sleeve retention
at all allow the throttle (butterfly) to get opened up all the way at all.
Sometimes the sleeve retention slips, sometimes the pedal cannot be depressed all the way.. sometimes it gets caught on the way ...

The easiest thing to do
On pic six you see the throttle stop screw...
get a friend or parent in the drivers seat and ask them to push the pedal all the way (engine not running)
if you see the butterfly resting against that screw, you'll be good.
If NOT, try to actuate the lever manually (the one under the tank is fine in case you removed the original throttle lever)
and if the butterfly get to that screw with it, you need to fix the throttle cable
(maybe a sleeve retention, maybe the pedal.. again: hard to tell from here)

But I'd almost make a bet that swapping to the correct belt,
will solve your problem already

'sid
 

950speed

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It isn’t symmetrical it’s an asemerric belt sorry for the spelling. And yes the cable goes all the way, I’ve gone over that and looked into it many times, it was one of the first things I had thought it might be. Also I am just curious if it could be the brand that makes the belt and it’s the right size, but the number is the same from a different brand, it’s what came with the cart and has fit properly all the time. But I guess from what you saying is it doesn’t fit properly
 

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I have to agree with Sid and also say that I think it is on backwards to boot! You should be able to read the numbers from the side.


Denny
 

itsid

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Oh yet another chinese misery belt.. packed with numbers for all different systems?
possible.. but look at the driven side,
beltissue_1.jpg
as far as I can tell
the belt top isn't flush with the sheaves.. (too narrow)
it's tilted slightly (wrong angle)

So either, it's indeed worn down and the wrong way around (as Denny suggested)
or the wrong belt (as I think) in both cases it needs to be replaced.

Since the edges aren't frayed I don't think it's worn down.. maybe the picture is deceiving
or my eyes play tricks on me... but how it sits in the sheave and the number...
too much of a coincidence to not trigger my impulse ;)

Oh btw: here a pic of a good belt for comparison


see? it's straight and flush with the sheaves..
that red one is a Manco Dingo.. and you can barely make out the number.. see? 5959 :D
(in fact it's one of those nasty twin number belts I mentioned earlier (203589/5959) but some are 5959 sized some are 203589 sized.. some are lucky matches ;))

'sid
 

950speed

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Oh yet another chinese misery belt.. packed with numbers for all different systems?
possible.. but look at the driven side,
View attachment 103332
as far as I can tell
the belt top isn't flush with the sheaves.. (too narrow)
it's tilted slightly (wrong angle)

So either, it's indeed worn down and the wrong way around (as Denny suggested)
or the wrong belt (as I think) in both cases it needs to be replaced.

Since the edges aren't frayed I don't think it's worn down.. maybe the picture is deceiving
or my eyes play tricks on me... but how it sits in the sheave and the number...
too much of a coincidence to not trigger my impulse ;)

Oh btw: here a pic of a good belt for comparison


see? it's straight and flush with the sheaves..
that red one is a Manco Dingo.. and you can barely make out the number.. see? 5959 :D
(in fact it's one of those nasty twin number belts I mentioned earlier (203589/5959) but some are 5959 sized some are 203589 sized.. some are lucky matches ;))

'sid
Ok so that’s one thing to add to the list, I’ll be ordering the belt soon,
But I still have no clue as to why the belt would make the engine big down
 

itsid

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As I tried to explain.. the belt itself doesn't..
the resulting lack of power does!

The belt causes the TC to be too inefficient to power the kart, thus the engine bogs down.

I'm fairly certain if you jack up the rear end of the kart, the engine revs nicely and all seems to be working just about perfect (minor issues perhaps with the TC not reaching overdrive but engine wise everything's good).
but as soon as there's load on the rear wheels it's not...

and that's a sure sign of power lack.. I could repeat myself (the gearing incorrect, wheels too large etc ) but with an incorrect belt, you effectively cut the motor power in half, which is most likely the culprit.

Truth is..
I cannot rule out there is indeed something wrong with your 'brand new' engine..
but what are the chances? (slim, right? not impossible, but very unlikely let's say)

Also, there might be something wrong with the TC other than just the belt
(maybe worn weights, overly streched garter springs, sticky clover hub etc.etc.)
The two buttons and the spring I can see in the pics are fine, the sheaves look decent as far as I can tell by the pics (bad angle to make a good call ;))

So yeah for now, the sticking out sore thumb is what I'll hit with that hammer ;)

Once you got the new belt, you need to disassemble the driver pulley anyways,
that's when you should take a look at the internals
and do some cleanup and relubrication (aka maintenance).
is the clover hub sliding freely in the moveable sheave?
is the wear limit mark on the weights still present,
are the garter springs okay,
is the pack the right way around,
does the brass bushing need to be replaced,
are the sheaves rusted and in dire need of thorough cleaning...

But since with the belt you have nothing would work well anyways,
let's just hope that's indeed all there is to it.

If you like, you can disassemble the driver now,
and in case you need replacements you can order them with the belt to save on shipping.
gokartsupply.com again or mfgsupply.com (also has belts of course)

as always: "when in doubt post pics" ;)

'sid
 

950speed

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When i lubricate it what kind should I use, I know it needs to be a dry lube but what kind would be recommended
 
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