BenJammin

Good to know. Thanks.

I'm kind of doing shot gun troubleshooting at this point.  I replaced the speed sensor, no change.  I bought an aftermarket carburetor and actually runs worse. 

Bought a brand new sparkplug coil. It measured 1.6 Ohms.  It was harder to start, backfired more and ran same as old one. 

Update: Correction, I did check valve clearance it is 0.00.  This Rotax 650 uses the shim type.  So not as easy to adjust. 

After some the recommendations about testing electrical components I decided to just follow the service manual. 

I've now check the rectifier for voltage at 5500RPMs = 15Volts=OK.  Manual states it should not to exceed 15volts.  Checked and measure the resistance between the Stator wire leads AC-1 and AC-2 = 0.6 Ohms. Should be 0.3 Ohms.  Checked continuity between Stator coils AC-1 to ground, AC-2 to ground. There was no continuity=OK.  Measured voltage across 2 of the Stator coils while turning over the engine, they each measure with the 4-6 Voltage AC range=OK.  Measured resistance on the Trigger Coil and it read 243 Ohms=OK.  Measure Sparkplug coil and it measured 0.6 Ohms. Not sure if this ok?

I hooked up separate gravity feed fuel tank and running it but still runs the same way. Tps out at 20MPH.

Using an external tachometer, if it is set correctly, I only reached 5500 RPMs.

FYI, I did make vides and load them to Youtube, so I know what I've done because my memory isn't the best.

I have not yet checked for breather hoses for vacuum leaks or this below.  I have it on blocks so once I get it off blocks I can try this. 

18 hours ago, Mech said:

You could try riding it in low gear till you hit the revs you do at 20 in high gear. If it keeps going past those revs then it says it's not a rev limiter.

Then if you rode it down a hill so it had no load on it, and it still wouldn't go over 20, then it really looks like being a speed limiter.

It's possible it has a speed(or rev) limit by design,  that you've triggered by accident, either in the wiring or the ecu repair. If you figure which limit it is, )if it is not a load limit), then it might be a lead where to investigate.

I'll check for a decompressor.  It does start and idle fine. 

Valve Clearance is suppose to be 0.015. 

Powers up 20 to no problem, maybe not full power compared to a Honda 500 I had.  No power or throttle left after it hits 20mph.  Speed is always the same.  It's a CVT transmission so I can't change gears only shift to high or low.  It could be limited at certain revs or throttle.  I can try and see if my RPM meter works on this type of coil. 

I have not tried doing a tune.  I blew out air filter.  I also ran engine without air filter and ran the same.  I've tried new sparkplug.   I have not checked fuel flow from the tank, valves, coil and cap for correct resistance and breather hoses for vacuum leaks. 

I've got some things to check,

Thank You,

Ben

I did a compression test on my 2005 Bombardier Traxter 650 CVT and it's 75 PSI.  service manual only talks about leak down test.  No specification for engine compression the manual.  What does 75 PSI tell me?  Thank in advance.

A little history of this machine.  640 miles.  Picked it up about 2 years ago, not running. Probably the computer.  Tested all circuits and confirm it was the computer.  Long story short, I watched a Youtube video and fixed the computer. ATV now started and runs.  BUT, it tops out 20 MPH.  I cleaned the carb 3 times also using a Mikuni carb kit after the second time.  Slide in carb is going up and down.  Only adjustment for fuel is at 1.5 turns out.  NGK Sparkplug had soot on main part but brown on the electrode.  Champion sparkplug is brown.  I check CVT clutches and they both appear to engage like they suppose to.  Checked valve clearance it's 0.00, I can't get any feeler gauges in-between.  I check timing chain I believe it's in the correct position and hasn't skipped.  I removed muffler plug and drilled into muffler to try and make sure it wasn't plugged.

The best way to troubleshoot your ATV is to get a service manual.  It will walk you through each step.  

Merry Christmas and Happy New Year!

I've worked on mowers and motorbikes for the last 4 years and a couple of snowmobiles and snow blowers.  I'm getting into ATVs. 

When in doubt restart. 

A friend of mine plows with a 1991 Polaris 350 TrailBoss. 

Has anyone used Fluid Film or something similar to undercoat their ATV?

Always make sure you have good gas first.  Float bowl could be stuck, clogged fuel filter or fuel pump. 

I use cheap kitty litter. Dry dirt form the driveway or cement.

Outdoor sports are fun!  More power to you.  I just started fixing them, I might get a few more as well.  Enjoy!

Good Morning and Happy New Year.

You might be able to find a new one on Facebook Market Place. 

CDI stands for capacitor discharge ignition

I'm in southern Wi.  Where about are you?

I bought a 2011 and needed it for plowing.  The guy I bought it from gets a new one every 3 years. This one had low miles.  I sold it and bough a Kawasaki Mule, but now place to put it for the winter, so I sold it.  Then  I bought a 2003 Honda Foremen 500 and wouldn't shift so I replace the shift motor and it works great. 

What code is it giving you?

What is the oil level? Is it hydro locked? 

Search internet for location of serial number.  Some ATCs are rusted out just like mine. Good Luck.

I just started working on ATVS, I have been working on mowers and motorbikes for about 4 years. 

Hello, I just started working on ATVs. Currently working on a 2003 Honda Foreman 500.  I am going to look at a friends 1991 Polaris Trail Boss 350.