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XR650R VERY hard to start, barely idles


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Hey guys-

I've been tinkering with a 2000 XR650R that I bought used a few months back. I've dumped some money into fixing it up a little, replacing the handlebars and all the controls, footpegs, brake pads, and other small stuff. It came equipped with a FMF Powercore 4 slip-on, that was dented and bent so bad that the rear fender was cut to clear it. I replaced the slip-on with a new FMF slip on, which appears to be the same thing, but with an updated spark arrestor.

I also cleaned and re-oiled the UNI filter that it came with, as well as cleaned up the airbox. The air filter cover was drilled by the previous owner. Since cleaning and re-oiling the filter today, the damn bike won't start without enough kicks to work up a sweat, and then it barely idles. Merely touching the throttle is sometimes enough to kill it, and then the kickfest resumes to try and re-start it.

I was careful to keep debris out of the carb, and to my knowledge, nothing else was touched. I do work as a Toyota Master Tech, and the bike sat in the shop today while I was working. It is a possibility that somebody "helped" and screwed with the carb, but it's pretty unlikely.

It ran fine before, but was always kinda hard to start. I've checked for fuel and spark, both were fine. Where should I begin? Check the jets? I can fix cars all day long, but motorcycles are new to me...

Ryan

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I would also check the clearance on your valves. Tight intake valves, which are a distinct possibility on a bike like yours that appears to have led an abused life, result in a bike that is very difficult to start.

I would pull of the tank to remove the carb and clean it, and since you are there, pop off the rocker covers and check the valve clearances.

Good luck!!

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Set them cold to factory specs. Covers have o-rings, no need for RTV. Just remove the two 8mm head bolts and there you are.

For me, the hardest part is getting my darn motor to stay on TDC. It always wants to roll back just a little bit. This is bad, as it engages the autodecompressor which puts pressure on an exhaust valve meaning you have to roll the motor all the way around again.

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For me, the hardest part is getting my darn motor to stay on TDC. It always wants to roll back just a little bit. This is bad, as it engages the autodecompressor which puts pressure on an exhaust valve meaning you have to roll the motor all the way around again.

Removing the spark plug keeps the compression from trying to back you off from TDC. The book tells you to remove the left side crankcase cover and use a socket to align the marks at TDC. Like Eastreich says, if the crank moves back even a little bit, the autodecompressor will engage and you will end up with that exhaust valve too loose. :eek:

Once you do it a couple of times it's easy.?

Check out this link:http://www.xr650r.us/tech/valves.pdf

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you said it ran fine before the air filter cleaning, is it possible you put too much oil on the filter and/or the wrong type? as far as always starting a little hard do a search on uncorking and jetting, should start 1st or 2nd kick.

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Check the kill switch. It's a known gremlin on the pig. Disconnect it at the wiring harness behind the front # plate. I had a guy trying to buy my stock carb in order to fix the problem's you are describing. I'm such a great salesman that I told him to check his kill switch first before buying my carb.... well, I still have the carb and his bike runs fine now. Hope this helps

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Checking the valves should be a part of every tune up.

The first and easiest thing to do is to change the plug. A bad plug can create a hard to start situation that can mimic carb problems.

It is also possible that you used too much oil in the airfilter which can create a too rich condition (flooding). Too much fuel not enough air.

Two other possibilities would be a broken main jet due to tightening it too much (I had one crack while tightening it and break completely when riding).

Or the float level is wrong. But a wrong float level will usually send fuel out the overflow when the bike is resting on the side stand.

I would clean the air filter and lightly oil it and change the plug out first. It is the easiest to check. A properly tuned XR650R will start on the first few kicks.

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Thanks for all the info guys!

I had a slow afternoon at work today, so I ran home and loaded the bike in the truck and ran back to the shop. I did a valve adjustment and replaced the spark plug, and inspected the carb visually for contamination.

I was very careful not to over oil the air filter when I installed it, so I was pretty sure that wasn't the cause. Checked and double checked everything, and tried to fire it up. Still no go...

Turns out, they run much better with some fuel in the tank...

Apparently, I forgot to check that, and it was simply just out of gas. Ran enough to ride from the parking lot into the shop yesterday, but didn't want to restart after the filter cleaning. I assumed something got screwed up since it ran fine before, and started thinking worst-case scenario. Sometimes even the best of us just need to keep it simple and check the basics...

Ryan

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So now that you have done all this work does it start any easier?

Starts on the 3rd kick cold, 1st when it's good and warmed up :applause:

The idle is still a little iffy, but I'm attributing that to using the old throttle cables and having to clearance the throttle tube to make it work. The throttle sometimes sticks just a bit off of idle, and causes a high idle situation. Usually snapping it a time or two will settle it down, but I've got new cables and a billet throttle tube on order that should sort that out.

Ryan

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  • 2 months later...
Starts on the 3rd kick cold, 1st when it's good and warmed up ?

The idle is still a little iffy, but I'm attributing that to using the old throttle cables and having to clearance the throttle tube to make it work. The throttle sometimes sticks just a bit off of idle, and causes a high idle situation. Usually snapping it a time or two will settle it down, but I've got new cables and a billet throttle tube on order that should sort that out.

Ryan

Wish mine was that easy to resolve. I got an 02 650. I wont start to save its own life. Its a low mileage bike...about 1500. Everything has been gone thru with the excpetion of the valves and carb. Will do that in am. But heck its a B I A T CH to start. :ride:

Air cleaner is clean. Oil new. Fuel fresh. Smog block off kit. Un corked. it pops when I kick it but wont run. Tried the wide open throttle deal it popped a few times then nothing. Im leaning toward floats stuck. Plug was wet when I pulled it. Yes It was a new plug. Where do I measure the floats? Ive read that they need to be raised? 2-3 mm?

Any help would be appreciated !!

TIA!!!

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Wish mine was that easy to resolve. I got an 02 650. I wont start to save its own life. Its a low mileage bike...about 1500. Everything has been gone thru with the excpetion of the valves and carb. Will do that in am. But heck its a B I A T CH to start. ?

Air cleaner is clean. Oil new. Fuel fresh. Smog block off kit. Un corked. it pops when I kick it but wont run. Tried the wide open throttle deal it popped a few times then nothing. Im leaning toward floats stuck. Plug was wet when I pulled it. Yes It was a new plug. Where do I measure the floats? Ive read that they need to be raised? 2-3 mm?

Any help would be appreciated !!

TIA!!!

Check this:

- Stuck float (the little shaft that holds the pivot in place can come loose, jamming the float, or, it could be stuck do to a worn float needle .

- clogged piliot jet- will never start with this

- coil ground wire loose

- plug wire oxidized where it connects to the cap;cut off and inch and re-install

- choke on

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Check this:

- Stuck float (the little shaft that holds the pivot in place can come loose, jamming the float, or, it could be stuck do to a worn float needle .

- clogged piliot jet- will never start with this

- coil ground wire loose

- plug wire oxidized where it connects to the cap;cut off and inch and re-install

- choke on

Im going to check all those things in am. Thanks again

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GOOD LUCK!

Found the problem.....

:busted:

I left a rag in the air box when I was cleaning-detailing the bike....

Let the flaming begin.....

Took it out.....bumped started it. Its been running fine since.

It was the first ride since I put the block off kit in....HOLY SH--

Wheely machine....

?

Next mod....

Jetting...and trip to MRD.

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