Hi everyone I am new to the world of gokarts , I just brought one for the kids and its giving me a headache , its about 10 years old and didn't want to rev up enough to move . I've replaced the carby and our a new Max torque clutch on , new plug and new electrics , I have now run out if ideas . if I jack the back wheels up it will very gradually pick up rpm but takes awhile to hit top revs . Any help would be great
6.5 engine probs
- Thread starter Shauns
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Denny
Canned Monster
And pictures of it would be even better! 
By the way
.
Denny
By the way
.Denny
How do I post a PIC , sorry first time on here
---------- Post added at 01:27 AM ---------- Previous post was at 01:09 AM ----------
Will post some pics tomorrow , the internet is way to slow here so will do it at work .
---------- Post added at 01:28 AM ---------- Previous post was at 01:27 AM ----------
Will post some pics tomorrow , the internet is way to slow here so will do it at work .
---------- Post added at 01:27 AM ---------- Previous post was at 01:09 AM ----------
Will post some pics tomorrow , the internet is way to slow here so will do it at work .
---------- Post added at 01:28 AM ---------- Previous post was at 01:27 AM ----------
Will post some pics tomorrow , the internet is way to slow here so will do it at work .
Welcome to the forum. It sounds like your gearing is off. Count the teeth on the clutch sprocket as well as the axle sprocket and post them here. Also give us the tyre diameter for the rear wheels. I have a feeling that you are geared too high
I took the exhaust off today ,for no real reason and it did slightly move it better but just will not get up into revs . NOt enough power to drive around the yard . I was thinking sprockets but then I ws thinking this thing is like 20 years old built by some old farmer guy with 1 tonne of steal you would think over the years they would have worked it out . The sprockets are also welded on so that's not going to be fun 
I will make sure I count them teeth when I get home
---------- Post added at 12:59 AM ---------- Previous post was at 12:57 AM ----------
Could it have anything to do with the governor ?
---------- Post added at 01:03 AM ---------- Previous post was at 12:59 AM ----------
Sorry everyone but one more thing ,how on earth do you work out the ratio with all those sprockets .. I know someone will know how to do it but I am just curious do you work it out on the ones coming off the motor or the other 2 ?
I will make sure I count them teeth when I get home
---------- Post added at 12:59 AM ---------- Previous post was at 12:57 AM ----------
Could it have anything to do with the governor ?
---------- Post added at 01:03 AM ---------- Previous post was at 12:59 AM ----------
Sorry everyone but one more thing ,how on earth do you work out the ratio with all those sprockets .. I know someone will know how to do it but I am just curious do you work it out on the ones coming off the motor or the other 2 ?
To work out the ratio with a jackshaft, you use this formula
(JS in/Clutch)*(Axle sprocket/JS out)
Post the tooth counts of all the sprockets and we will calculate it for you. The only reason that the engine was slightly better with the exhaust off was because it could breath better. That is why a freeflow exhaust and intake is recommended to get a bit more power out of the engine
PS. JS stands for jackshaft. Those back tyres look big. You might have a problem there if the gearing is off. We can only tell though once we are sure of your ratio
(JS in/Clutch)*(Axle sprocket/JS out)
Post the tooth counts of all the sprockets and we will calculate it for you. The only reason that the engine was slightly better with the exhaust off was because it could breath better. That is why a freeflow exhaust and intake is recommended to get a bit more power out of the engine
PS. JS stands for jackshaft. Those back tyres look big. You might have a problem there if the gearing is off. We can only tell though once we are sure of your ratio
So that makes your gearing (48/10)*(40/16) = 12:1
Your gearing is low enough in my opinion to not be having the problems you are experiencing. Even with 17 - 18" tyres. Are you sure that when you push the pedal all the way that the cable is actually engaging the throttle fully? Sometimes there is slack in the cable that only allows the throttle to open halfway, even though you have the pedal to the metal. Have someone stand behind you looking at the engine while the pedal is pressed. Does the engine throttle get opened fully?
Yup, post a vid and maybe we can see something. It could maybe be your clutch that is toast
Brand spanking new clutch just fitted yesterday , wasted 100 dollars because that's what I thought the problem was . I thought the clutch was engaging to soon and therefore wouldn't let it rev . what's really confusing me is even if I jack up the back end it still won't rev ul straight away it takes a few second to wind up but once it's up in the revs you can keep fanning the peddle and revs how its supposed to
Any kart on stands will rev up ok....it is when it is under load that you have to check it. Post a vid of you revving the engine while on stands. You can also try get a tach and see if you are revving to 3600RPM's
KartFab
Active member
Could also be a partially blocked carb-lean
improper valve lash-loss of compression
and/or bad ring seal -loss of compression
Id clean out the tank fuel line and carb before I did anything else
improper valve lash-loss of compression
and/or bad ring seal -loss of compression
Id clean out the tank fuel line and carb before I did anything else
Hi thankyou for the feed back , fuel tank drained ,new fuel line new carbie . Thought maybe the new carbie is a defect so put the old one back on and ran the same . As far as rings go I would have thought it would be blowing smoke if rings where no good ? valve lash etc. I have no idea about that stuff . One more thing I should mention is the spark plug is very black (new plug) . Oh well hopefully this afternoon I can get a video of it running .
mckutzy
Well-known member
You mentioned you replaced the "electrics".... does that also meant the coil aswell??....
Is the coil gapped correctly? ....... About 2 buisness cards thickness in between the coil and the flywheel.
Is the coil gapped correctly? ....... About 2 buisness cards thickness in between the coil and the flywheel.
FreeRunner15
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LIKE THAT TOP-SECOND PIC!
i need that for an example for my jackshaft. i'm going to use your pic.
Denny
Canned Monster
Stupid question time, How hard is it to rotate the drive wheels when they are off the ground? Are any of the bearings froze up? 
Denny
Denny
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