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Just got an '05 at the beginning of June. I check the valves and shimmed to bring into spec. I also rebuilt the carb. This thing always takes a dozen or more kicks hot or cold. If it has been run then shut off it takes forever to get it restarted usually bump starting is why quicker. Help me this thing is kicking my rear end.

Brad

Welcome to the site !!

So when you say you checked the valves , and rebuilt the carb , was this back in the beginning of June ? , and you have not checked or done anything since correct ??

If so , was it ridden much during that time or just mostly sitting ??

Did you put FRESH gas in it since June ?? , so basically , has it had fresh gas within the last few weeks ?? , or is the gas in the tank/carb , gas that has been there for a while (a few months??)

What does the bike do when you use the Hot Start Lever ?? , does it make any difference if you use it or not ??

Does the bike backfire a lot on Deceleration ??

Did the bike have this issue since you bought it ?? , or was it fine then it just got worse and worse ??

What is your current jetting ??(Main Jet , Pilot Jet and Needle Clip Position *from the top* , and Fuel Screw Setting **from all the way closed to where it is set**) , and what is your elevation that you live/ride at ??

When you "rebuilt" the carb , what exactly was done to it ??

JimDirt wrote:Welcome to the site !!

So when you say you checked the valves , and rebuilt the carb , was this back in the beginning of June ? , and you have not checked or done anything since correct ??

If so , was it ridden much during that time or just mostly sitting ??

Did you put FRESH gas in it since June ?? , so basically , has it had fresh gas within the last few weeks ?? , or is the gas in the tank/carb , gas that has been there for a while (a few months??)

What does the bike do when you use the Hot Start Lever ?? , does it make any difference if you use it or not ??


Does the bike backfire a lot on Deceleration ??

Did the bike have this issue since you bought it ?? , or was it fine then it just got worse and worse ??

What is your current jetting ??(Main Jet , Pilot Jet and Needle Clip Position *from the top* , and Fuel Screw Setting **from all the way closed to where it is set**) , and what is your elevation that you live/ride at ??

When you "rebuilt" the carb , what exactly was done to it ??

I have not put new gas in it. Are these bikes really that sensitive.

Carb rebuild. New needle, jets and gaskets.

The valve were shimmed last week.

It was hard to stRt when I brought it home.
Don't know if the hot start makes a difference it seems like I kick for an eternity whether I have I pulled or not.

It does pop a few times when first started back that seems to diminish after riding briefly.

Thanks
Brad

I changed the fuel ou, and bike starts much easier. I can't believe it is that finicky. Now I have a new problem. It seems to overheat riding in the woods following my kids. Any good fixes?

Thanks
Brad

I have the same bike.
After re-shimming the exhaust valves the bike runs way better (although havent rode since april lol).
Also there is a bit of a "special" way to start the bike.
- choke on
- hot start pressed
- 2-3 squirts of throttle
- kick it

Seems to work on mine 5-10 kicks.
Mine heats up quite a bit if leave it sitting.
On the single tracks have to really try and husstle because if not allot of fresh air hitting the rad it heatrs up quickly. If you come to a stop almost for sure shut her off becuase will start to overflow.

These bikes will easily overheat if left running at idle. They want to be moving. This will be even more of an issue if you're fuel mixture is lean. What size jets did you put in the carb? You want a 45 pilot. Have you checked your TPS sensor to ensure the reading is correct? Did you measure your float bowl height with a proper gauge? Is your fuel screw 2 turns out from fully closed? Is your hot start plunger returning to the fully closed position? Hot start cable adjusted properly? Idle screw set properly? Did you replace the floating valve seal when you rebuilt the carb? As you can see, there are a lot of things that need checking. And yes, these bikes are that finicky.

If your going to ride woods, then you need to make sure of a few things

Momentum , is key , as mossman77 mentioned , these bikes need air flow to cool , if your not moving much , your not flowing air thru the radiators

Engine Ice , it will help keep the radiators from boiling over as easily

A 1.6 or 1.8 Bar Radiator Cap , this will allow the temps to get a bit higher before it pukes out coolant

And as mentioned , the correct jetting , if your jetted too rich the bike will overheat , and if your riding slow and the bike is running hotter , try going one size DOWN on the main jet , leave the pilot at #45 , leaner jetting with hotter temps (ambient temps , not engine temps) will run cooler

Higher octane gas will burn cooler as well

Also there is a bit of a "special" way to start the bike.
- choke on
- hot start pressed
- 2-3 squirts of throttle
- kick it

Seems to work on mine 5-10 kicks.

My brother-in-law has an '04 250R and one of the intake valves is zeroed out and the other is at 0.003". Even so, the bike runs great once you get it started (problem is getting it started). I was visiting his house this weekend and he said that the bike was sitting for a few weeks and he could not get it started last time he tried. He would kick and kick and kick, but nothing. I decided I would give it a try. I put some fresh gas in it, but that didn't help. It didn't even sound remotely close to starting. I then attempted to bump start it as I've done in the past when it wouldn't start. Finally, after about 10 tries, I got it started. Once it warmed up, it would start on the first kick when I followed the tried and true method (find TDC, whack throttle to prime, then kick hard). However, if I let it sit for a while, it would not start and I would have to revert to bump starting again. While doing so, I messed with the idle screw to see if that would help. I turned it CW about two full turns to open the slide further and that did the trick. However, once it started, it would be idling too high (understandably). I decided to try something else instead because bump starting was wearing me out. I put the idle screw back to its original position and instead held the throttle open slightly (which accomplishes the same thing, only temporarily) and it started first kick every time!

I felt obligated to share this because I have seen so many posts about valves zeroing out and people not being able to start their bikes. Sure the bike needs a new top end, but at least there's a way to get it started in the meantime. Here is the sequence that works for his bike:

1) Rotate kick starter to find TDC (listen for auto decompressor click)
2) Pull out choke plunger (even if it's hot outside)
3) Whack throttle quickly four or five times
4) Hold throttle open slightly and kick hard

The bike started right up every time on the first kick, even after sitting for an hour. The key is opening the throttle slightly. I also experimented with using the hot start lever, and his bike doesn't like it (the engine dies). I'm sure many of these anomalies are due to the fact one of his valves is zeroed and the other at 0.003". He definitely needs a new top end, but in the meantime, this starting sequence is working. Hope this helps someone!

My 06 currently is a lot like this, and was able to make it a bit better with a good carb rebuild. I decided to just put a new top end in the bike since it was abused by its prev owner, and I ride it like hell, but I try to take care of it to the best of my ability.

I find also a few squirts of the throttle like everyone else is saying (2-4) and just a slight amount of open throttle with the choke on can start the thing hot or cold on the first kick or after 6-7. Since it's just gonna get worse, and I don't like kicking if I don't have to, it's getting a whole new top end.

On the heating, I just put bigger aluminum radiators I got off of ebay which have made a massive improvement on the heat issue. The stock radiators are kinda thin, and I live in a desert so I always replace the radiators on my toys/vehicles to the biggest ones I can get. With the big aluminum ones I am running I can put around slow and have not noticed any heating issues like on the stock radiators. Might be something worth looking into.

Thanks for all the responses