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Hard starting RMZ 450

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Guys,

        I have a 2008 RMZ 450 with EFI.

 

The bike has maybe 10 hours on a brand new crank, piston and rings, and cylinder. 

 

It is hard starting.  I have checked the valve clearance twice.  Cold it does not want to start.  I kick like crazy until it finally fires.

 

The choke never really did much on the carb.  I always had better luck starting it with the choke off all together.

 

Lately it doesn't want to start at all.

 

I sprayed quick start in the spark plug hole and it started right up.

 

I really think it's a fuel issue.  I don't think it's getting gas to the cylinder. 

 

Spark is good.

 

Once I got the bike running and hot it was fine and restarted no problem.

 

Is it possible the EFI is not working properly?

 

Any suggestions?

 

 

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Well, it's possible your idle isn't started right or one of your injectors is dirty. How are you starting it?

Always kick it from TDC and it should start in a few good kicks.

Do you also put all your weight into it?

By the way, it's a throttle body, not carb :p

The choke should work fine. My '12 always starts 2-3 kicks with the choke out from TDC.

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Is the motor stock or is it modded. Any chance there was a fuel controller on the bike prior to you owning it or are you the origninal owner? Are you kicking from TDC? TPS check out? I would consider cleaning and using dielectric grease on all electrical connections as well. These are all cheap and easy to check.

 

If everything else checks out I would think about having your ECU remapped.

 

If it starts immediately with Ether I would lean towards a gummed up injector, or a mapping issue.

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Guys,

I have a 2008 RMZ 450 with EFI.

The bike has maybe 10 hours on a brand new crank, piston and rings, and cylinder.

It is hard starting. I have checked the valve clearance twice. Cold it does not want to start. I kick like crazy until it finally fires.

The choke never really did much on the carb. I always had better luck starting it with the choke off all together.

Lately it doesn't want to start at all.

I sprayed quick start in the spark plug hole and it started right up.

I really think it's a fuel issue. I don't think it's getting gas to the cylinder.

Spark is good.

Once I got the bike running and hot it was fine and restarted no problem.

Is it possible the EFI is not working properly?

Any suggestions?

From what your saying, runs fine once hot and needs extra fuel when cold to start. To me seams like coolant temp sensor my not be reporting correct temp. Since motor apart last 10 hrs, I would double check connection there, and wiring routing. An unplugged or loose connection, or a chaffed wire rubbing on frame would skew the sensor reading enough to cause problems. On fuel injection the coolant temp reading is your choke. Computer will hold injector open longer to add more fuel when it reads cold. Oh yeah, the traditional choke knob your referring to, I believe is for higher idle speed only. Since there is no way on these bikes for the computer to control the idle, it lets you do it by pulling knob out, and letting more air past throttle plate. Again to aid in cold start situations. Edited by Yamkifour

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Guys I solved the problem tonight.  I was going to pull the fuel injector and try the 9 volt battery trick to clean it.  Before I got that far I looked at my fuel line.

 

The fuel line is nothing more than cheap car fuel line with a rubber cover on it.  The fuel line was kinked in one spot so bad it was cutting of the fuel.

 

I run an aftermarket high capacity fuel tank and must have spun the line around the wrong way the last time I changed the spark plug.  You can't get to the plug with this oversize tank on.    I saw other people with the same issue this may be the problem so beware the cheap Suzuki fuel line.

 

I started the bike in about 3 kicks in my flip flops after I fixed the problem. :ride:

 

 

I have a good picture of the kink but I don't know how to upload pics to TT.,

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