LT80 won't go?

[mikeman828]

Hey guys, gotta a problem with my son's LT80, can you help????

Here's the scoop...

He started it up yesterday to take it for a spin and forgot to turn his gas on. He went down one of the trails in out back yard and it sounded like it was running with the choke on. After a minute or 2 I heard him talking to his brother that when he gives it gas, it does't go. I went down to him, turned the gas on and tried again... when you give it gas it doens't have enough oompf to move the quad!!

I brought it up in the garage and jacked up the rear end, turned it on and gave it gas. It got the back wheels turning, but not fast at all. I did this a couple of times, applying the brakes and gassing it up again... the same.

Could he have wrecked the piston riding w/o the gas on??
Is it a belt/pulley that went??

Any thoughts??????

:confused:

[LT80]

I think there is something in a jet. Clean the carb.Remove both jets and the brass piece that the float needle sits in and clean well.
If that don't do it, let us know. We'll go from there.:)

I'm curious. Do you have a on/off shutoff in the fuel line or posibly a banshee petcock? Other than that, (on a stock petcock) in the run position the fuel flows when the motor produces vaccum to the petcock,when not running it is shut off. Altho it will fail on occasion to shut off. In prime, the fuel flows all the time.

[mikeman828]

what about a fouled plug???

Do you think him riding with no gas, but oil injection could have caused a fouled plug??

I'm gonna pull the plug today when I get home and put a new one in, but I'm not sure that is the cause..

If you foul a plug isn't it a bear to start and keep running? His LT starts right up..?

If the plug looks good, I'll pull the carb like you suggested.

I'll let you know what I find.... thanks for the reply.

To answer your other Ques... it's a stock petcock. When he rode it was shut off, I turned it on after the problem occured and there was no change. No other shut-off that I'm aware of....

[LT80]

A new plug can surely be tried. BR8HIX is what I recommend.
At the last GNC TT race my rider did indeed have a bad plug.
But 9 out of 10 times, it's a plugged jet.
You are correct that a fouled plug make for hard if no start.
The fact that it starts tells me the pilot jet is working,but when you try giving it throttle, the motor is sucking air and no fuel.Pointing to a plugged main jet.

Petcock: That's my point, there is no off position.
FYI:
<-- is reserve (low fuel in tank) ---> is prime (fuel will run constantly)
Down is run. In the run position, fuel will not flow when the motor is not running. When the motor gives the petcock vaccum, it opens the petcock and allows the fuel to flow. ;)
Hope that helps :)

[mikeman828]

My son's petcock has a on/prime/off position indicator on it. Off is pointed sideways, like other petcocks.....does that make sense??

Maybe It still lets fuel go, but what's the use of having it say OFF!!

Maybe it's not a stock one? The machine is used....

I didn't have a chance last night to pull the plug... I'm going to tonight.

Thanks for the help....

[LT80]

Well that explains that! :D :D
I'm guessing that you have a banshee petcock on it then. It's a good and less expensive way to cure a petcock problem on the LT80.

[mikeman828]

Hey LT80,

Well, I finally got around to working on my son's LT80 yesterday.
Here's what I found while working on it...

The plug was fouled BAD! Caked with oil and even some build-up on the electrode from it. Also, it was loose!! I could wiggle it a little and unscrewed it by hand. So, I put a new stock plug in and tightened it down pretty well.

After I went to the air filter, it was nasty!! It was clogged with mud and junk... So, I pulled it out, cleaned it, cleaned the airbox and re-installed.

Then I went to lube and clean his chain, just cuz I was in the maintainence mode.... His sprockets were pretty worn and the chain was so loose that it was "trying" to jump teeth on the front sprocket!! I am ordering a new chain and sprockets today.

This is a used quad and obviously I didn't check these things when we got it, cuz irt was running fine... I also picked up a shop manual for it.

So, I wanted to thank you for the help and input you've given..


p.s. I do have the stock petcock. I must have read it wrong before...

:D

[4punksdad]

the lt is very sensitive to a clogged air filter. Also, there is a small rubber hose that goes from the carb to the crankcase area (not sure what it does) but it will cause the same symptoms.

[efilnicafesin]

Originally posted by 4punksdad
the lt is very sensitive to a clogged air filter. Also, there is a small rubber hose that goes from the carb to the crankcase area (not sure what it does) but it will cause the same symptoms.


Really?? My tab is broken off the case and just flopping in the breeze :o .... guess I should put that on my fixit list....

[4punksdad]

Originally posted by efilnicafesin
Really?? My tab is broken off the case and just flopping in the breeze :o .... guess I should put that on my fixit list....

yup..........sounds like it could be part of your problem. JB weld should hold it in place.

[mikeman828]

Me again,

Well, I got my son's chain and sprockets on. Took it outside fired it right up, runs great.... motorwise! It still won't move!!! When the rear wheeels are raised it gets them spinning, not overly fast.
When I put it on the ground, and have my son sit on it.....it will not move the quad!!!!!

Is there any checks to do for the clutch??? Could the drive belt be stuck in the fast speed setting??

What kind of ideas do you guys have??

LT80, are you out there?? Your expertise would be appreciated!!!

HELP!!!

:confused: :confused:

[4punksdad]

I have never had this problem. Is it revving as if the clutch is slipping? or is it lacking power to move?

[mikeman828]

The motor seems to be strong... revs good and accellerates w/o any problems. Undeer no load though!!!! I don't have acompression gauage to check compression, but I don't think it's that. Did you read my original post to get an idea on what I have for a situation??

Ideas??

[4punksdad]

#1 fix that hose from the carb to the case........

#2 pull the fuel line from the carb end and check for flow on all petcock settings. The lt 80 has a fine screen on the petcock that might need to be cleaned.

#3 drain the bowl and tank for bad fuel.

#4 check the belt drive.

I have had several 80's and never had to adjust or replace a belt or clutch, but I have lost power due to the items mentioned above. In most case mine never acted like a slipping clutch, more like a power loss.

If none of this works, try the mini forums at www.cannondaleriders.com for some good info from the pros.

[LT80]

I still think a good carb cleaning is in order.A plugged jet can make it do what it's doing.
After that, I feel that you should do clutch maintenence.Check the rollers for flat spots and other wear in the front clutch.Squeeze the rear clutch to see if it will move.
Borrow a compression gage.I got mine from sears for like 20$
We'll go from there.
FYI: that lil tube by the right foot that runs from the air box to the fan cover::: you can fix it but it has nothing to do with the way it will run.

[mikeman828]

LT80,

OK, I'll start with a carb cleaning... it's a little easier than pulling the case off to check out the CVT anyway.

Hopefully you're right an that will cure it...

Thanks for the help.:D

[mikeman828]

Well, I spent last night pulling the carb off and cleaning it....

There was some junk in it, so maybe you guys are right on!!
Hopefully!! I also pulled out the throttle cable limiter, which should give him some good top end..

I'm just waiting on a new gasket for the bowl, then I'll slap it together.

I hope this works!! I'll let you know how I make out!


:D

[4punksdad]

I didn't know we were talking about a bike with the throttle limits still in place. Remove the washer in the headpipe and the srew in the thumb throttle while you are at it.

[mikeman828]

According to the guy I bought it from, he already removed the exhaust restrictor.... maybe I'll pull the pipe off and make sure.
Bolts are pretty damn rusted though... hopefully I can get them off.

PB Blaster still the best for loosening rusted bolts??

:cool:

[4punksdad]

hot exhausts suck to work on, but the bolts break loose much easier. If I remember correctly, the washer is between the headpipe and the silencer.

[efilnicafesin]

You really don't want to loosen old bolts in aluminum when it is hot. There is a good chance that you will pull the studs out and strip the threads in the process.

If you get the engine hot, then spray the stud with a rust penetrant, it may help in breaking it loose. By spraying just the stud, you are cooling it quicker than the nut and it will actually break the rust bond. This method does work, but it smokes like heck.

[4punksdad]

Originally posted by efilnicafesin
You really don't want to loosen old bolts in aluminum when it is hot. There is a good chance that you will pull the studs out and strip the threads in the process.

If you get the engine hot, then spray the stud with a rust penetrant, it may help in breaking it loose. By spraying just the stud, you are cooling it quicker than the nut and it will actually break the rust bond. This method does work, but it smokes like heck.

the headpipe and silencer are not aluminum.

[LT80]

But the cylinder is made out of aluminum, I think that was what he was refering to :)

[4punksdad]

Originally posted by LT80
But the cylinder is made out of aluminum, I think that was what he was refering to :)

for this washer to be removed .................NO nuts or bolts are in contact with any aluminum.

[Mxjunkie]

Originally posted by 4punksdad
for this washer to be removed .................NO nuts or bolts are in contact with any aluminum.

yeah your correct, this will give your son some more speed and top end/power :macho we took mine off my lt80 right when i got it

what might be causing the lt to take off slow etc might be your belt for your clutch, we fryed alot of them with my lt and it did the same things, just an idea though

[mikeman828]

what might be causing the lt to take off slow etc might be your belt for your clutch,

That's where I'm headed next if the carb cleaning doesn't do anything. I really don't want to go pulling the side cover off the case though.....

Oh well, we'll have to see how things turn out with this first.

I'm hoping to get it back together tonight tomorrow AM so we can try it out

[efilnicafesin]

Originally posted by LT80
But the cylinder is made out of aluminum, I think that was what he was refering to :)

Yes, that is what I was referring to...

On my stock exhaust, it is one piece from the head pipe to the little POS tailpipe. Where is this washer/restrictor you are talking about? and how do you get into the exhaust without unbolting it?

Isn't this the exhaust you are talking about? This one has been modded a bit, but still one piece..

http://i16.ebayimg.com/01/i/02/35/e7/7b_1.JPG

[mikeman828]

that looks like the same basic exhaust I have....just cut a little

the washer is supposed to be in between the pipe and the cylinder. They put it there to restict the flow of exhaust out into the pipe, why I don't really know....

You do need to unbolt the pipe to get access to it.... the other restrictor is in the carb.

[mikeman828]

Well I cleaned and rebuilt the carb, also checked the exhaust to see about the restrictor plate...... NO DICE!!! Itis still doing the same thing!!

When I give it gas it starts moving enough it seems like it's rolling, then when I reach a gradual incline it stops moving. The engine has no affect on it moving...... if I start rolling the gas slowly, it starts to move, then reaches a gradual roll and that's as fast as it goes!!

What are the best ways to get into the belt/clutches???

Do I have to rip the side case off to get at the belt/clutch??

What should I look for???

Anyone?

Thanks for the help guys!!

:confused:

[mikeman828]

Well my son and I worked on his quad yesterday... we pulled the small cover off the CVT side of the case. We started it and tried to see any problems inside the cover. one thing that we did find is a noise coming from inside the case.......

It sounded like someone dropping a wrench on the ground!! It occurred whenever we gave it gas to get it moving!! When I was walking next to the quad I could get it moving, but when I was sitting on it, it wouldn't go.... only make the noise and keep revving. It sounded like it was coming from the clutch, is this normal??

Does anyone have any ideas about this noise????

I pulled the cover off the CVT side last night, but I don't have the tools to remove the clutch, so I wanted to get some feedback on what could possibly be happening. There was a little crappy water inside the case, could this have caused something to rust and/or breakdown??

HELP!!

:confused:

[mikeman828]

Well, I finally found a compression guage and did the compression test last night. It was about 120-130psi.
From what I've heard about motors, that's good. Plus seeing as it's a 2000 and still has good compression made me feel pretty good about the condition of the motor.

Now on to the belt/CVT..... anyone got any tips for removing the clutch???? what do I look for if I have abad belt??

Thnx

:D

[efilnicafesin]

How did you make out? Is it up and running?

[mikeman828]

No not up and running yet....

I've been busy as soccer season for my kids is wrapping up. Haven't had a lot of time to work on it.

Right now, I'm trying to get the front clutch off. The manual says to take the fan off the opposite side of the engine and hold the crankshaft while loosening up the clutch nut. I've been working on getting the fan screws out, they are loc-tited in and don't come out easily.

Other than that the rear clutch is all loose and ready to come off, just need the front one to come off too so I can slide the belt off.

I'll be diving back in again real soon, soccer is done and I want to ride...... so does my son!!

any tips??

:D

[efilnicafesin]

I haven't had mine apart, so I'm not too sure about the setup, but if they want you to remove the fan to get a spot to hold the crankshaft, you may be able to use an impact gun of the clutch nut? The impact gun will loosen the nut without the shaft turning. Like I said though.. I haven't seen the shaft, so I don't know if there would be any adverse results to using the impact gun.

[mikeman828]

thanks... I'll look into that....
it would help!!!

:D

[mikeman828]

Just wanted send a post and update on the problems with the LT80 I had (or didn't have).

I had it all apart ready to work on the clutches, but tool resources ran out and I couldn't get the clutches off to pull them apart. So, I decided to clean everything I could possibly see, think of, and then I reassembled everything hoping for a miraculous fix.....
Well, it worked! I got it all back together and fired it right up, took it outside and the thing ran mint!!!

I don't understand what was wrong, maybe some dirt or crud on one of the drive faces causing the belt to slip... something causing the clutch to slip, I dunno. Anyway, instead of bringing it to a dealer like I was expecting, it is up and running great.

I am still baffled by the problem, but not complaining that it is fixed......

Thanks for everyone's help and suggestions.

:D