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yz250f decompression cam

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Hi guys, hope that someone can help me, My friend took his 02 yz250f into a local shop and had a decompression cam installed. They also did a "tune up". He got the bike back and can't start it. I brought it to my house to look it over. My first thought was jetting. I looked at the jets, all stock, clip on 4th position, screw 2 turns out.

The plug was not replaced in the "tune up" it was showing signs of a rich condition. I installed my spare plug, went through the starting procedure ( I have a wr250f), so I know how to do it. It still won't start. Took the plug out again and it looked dry(no fuel).

I also took the valve cover off just to check the timing on the cams. Counted 12 pins. All good. What I did notice thuough was that they left the old decompression mechanism in the head, I thought there was a plug that had to be installed. Does anyone know if this will affect anything? I assume that the plug is to go in the mechanism hole?? Will the bike run like this?? help??

sorry for the long post, but more info is better than to litte.

Thanks

Jeff

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sorry can't help on the problem, but i'd seriously find a new dealer if they didn't also remove the mechanism and don't include a simple two dollar 45 second spark plug change as part of a 'tune up'

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you dont have to remove the lever thats in the head. But make sure it still has the spring on it to make sure it releases. Most likely it does.

There is no starting procedure for auto decompression cams. just kick it until you turn blue and decide to determine why it isnt firing. :cry:

I would look for pinched wires from them putting the tank back on.

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Hi guys, hope that someone can help me, My friend took his 02 yz250f into a local shop and had a decompression cam installed. They also did a "tune up". He got the bike back and can't start it.

let's stop right there.

the way i see it:

bike ran OK.

dealer worked on bike, and got paid for parts and labor.

bike doesn't start.

hmmmmmmmmmmmmmm. you know who i'd be talking to?

jim aka the wrooster

'01 wr250f

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It could be user error; with the auto decomp, you don't push it over compression and then kick, you push up against it and then reset the crank and kick it (although with a 250, you can just thrash away at it, it's just a little more productive the other way).

As far as removing the original lever, that requires draining the coolant (a shop has to treat coolant as hazardous material, by the way) so you can get the right radiator out of the way. If it was me I would have charged extra for that.

Spark plugs don't cost $2, either.

Nonetheless, Wrooster makes a point. I would certainly hope that the tech who did the job tested it afterwards (he'd have caught hell from me if he didn't), but even if it ran when he shut it off, he should take another look for you after doing a "professional" job.

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how much do you pay for plugs? i was speaking of what it would cost the dealer, our cost on them is $2.60... but that wasn't my point, my point is a good dealer if doing a tune up wouldn't over look something so quick and cheap and i know removing the mechanism isn't necessary, but i would hope by now the dealer had done enough of these to be familiar with the full procedure and do it 100%, those two things together sounds like the dealer is pretty lazy and not the type of place i'd get work done

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I worked in or managed dealership service departments for 34 years, since you asked, and I was damn good at both. Sorry, it's just the facts.

If your employer pays $2.60, he'll have to sell it for at least $5.20 to keep his profits at any kind of respectable level, unless he uses plugs as a loss leader. Secondly, the fact that a customer asks for a tune up is no reason he has to be charged for a part that doesn't need to be replaced. Mind you, I'm not saying it did or didn't, because neither of us knows, but giving the benefit of the doubt, there may well have been no need to be, and there is nothing to indicate that it was "overlooked".

"Tune up" is a term that I think is misunderstood, misused, and misleading in many cases. In a major tune up, for example, you should check and adjust the valves (would you charge the same price on a YZF if it needed no adjustment as if it did?), change the plug (what if there's nothing wrong with the one in place?), check the timing (interesting, but it can't be adjusted, so unless you're going to replace the component that's causing it to be wrong, it takes almost no time), adjust the fuel screw (which will need to adjusted again when the weather changes), and clean the air filter. Did I miss anything? If not, how much do you guys charge for opening and closing a cam cover, shining a strobe light in a hole, tweaking a idle screw, and cleaning a filter?

In motorcycle service, as in automotive service, too many people are too willing to buy something they don't need based on their own "diagnosis", and there are far too many people willing to sell it to them. It would be better, instead of asking for a tune up, to pay a good wrench to look the bike over for an hour and a half and see what he can find that actually needs fixing.

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maybe you missed what he said in the thread

"The plug was not replaced in the "tune up" it was showing signs of a rich condition"

and your right on retail is exactly $5.20, but thats not the issue

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Maybe you missed the fact that he checked it after spending an extended period of time failing to start it.

And that no one said why it wasn't replaced.

You can't read rich or lean on a plug from an engine that doesn't run, unless you mean by a "rich condition" that it was wet.

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My dealer put my 03 cam in my '01 with no problems, I had him leave the decomp assembly in. No re-jetting was required. However, if you do decide to take it off and plug it, get the trick plug here. I did see an '03 at a track loose the stock plug. See the FAQ.

Some members have reported "loosing" the decomp plug after doing the mod. This leads to oil spewing out of the head. This would seemingly then also be a problem on the 2003-2004 models but has not been reported. TT member Vibeguy is making a trick aluminum plug that replaces the decomp shaft and is held in by the retention screw. With this option there is no need to buy the blanking plug. The decomp plug is available online at the TT store.

http://www.thumperfaq.com/autodecomp.htm

:cry:

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As far as removing the original lever, that requires draining the coolant (a shop has to treat coolant as hazardous material, by the way) so you can get the right radiator out of the way. If it was me I would have charged extra for that.

This is not correct. The only reason you have to "move" the radiatior is to get the cable out from inbetween the frame and the radiatior. You only need to loosen the mounting bolts to accomplish this. You do not have to "remove" the radiator.

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FYI...We have a sporting goods and Auto part store here called G.I. Joes. They sell spark plugs for $2.19 and every other week put them on sale for 20% off of that. If you have a GI Joes in your neck of the woods, check it out. They have also started carrying bike and atv accessories, oil and such, good prices on all.

Shane

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O.K.

Basic troublshooting 101:

A:does the bike have fuel in it? Is the fuel getting to the carb? If the spark plug is wet chaces are fuel is getting into the combustion chamber. You can also remove the air boot on he carb and whack the throttle(only once) and watch for a squirt from the accelerator pump.

B:Are you getting spark? Take a new plug and put it into the cap, ground the plug against the cylinder and kick a few times. You should see a blue spark jumping the electrode.Do this with an extra plug and leave the original in the head. Yeah,you will fight the compression a little but it keeps the fire hazard down!

C: does the bike have compression? Dont be fooled by the internal pressures of the valve train,test it with a gauge!

If you have all three parts in the right sequence the machine will run.

In this case I would suspect a cam timing issue.I cant see a dealer servicing a bike and not having the thing run afterwards.Dont go back to that dealer. :cry:

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Hi guys thanks for all the tips and such, I did go back out to the bike after I my orignal post, I went thru the jetting and the air screw settings again, and I set it up like my WR.

I climbed on whacked the throttle a few time and it fired on the second kick.

About three weeks have past since the time that the dealer has had the bike, and when I picked it up from my buddy. In that time the temp has dropped quite a bit... I'm in Canada eh! I think that it was mostly air screw adjustments that I needed to make.

Wrooster I hate taking my things in to be serviced, I don't trust dealers and feel that although I am not a mechanic, but am an electrician, I'm use to mopping up after the maintenance mechanics here at work. I'm very capable of doing my own repairs. I wanted to to do the whole job for my friend, but he couldn't wait for me to do it so he took it to a local Suzuki dealer.

Cheers guys,

And if anyone is interested in banging bars up here in the great white north sometime, send me a message.

Jeff :cry:

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Another term for an electrician is someone to diagnose the fitters and mechanics faults for them after they have claimed it to be electrical , :cry: , am a sparky as well and just chucked in the yz cam into my 01 wr have just been fiddling with the carb to tweak it but it sure starts like a gem now . I think they got to put an Aussie flag in with the instant graemlins , cheers

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As far as removing the original lever, that requires draining the coolant (a shop has to treat coolant as hazardous material, by the way) so you can get the right radiator out of the way. If it was me I would have charged extra for that.

This is not correct. The only reason you have to "move" the radiatior is to get the cable out from inbetween the frame and the radiatior. You only need to loosen the mounting bolts to accomplish this. You do not have to "remove" the radiator.

On my '01, the shaft, which looks to be a good 1 1/4" long is about 1/2" away from, and perfectly lined up with the crossover between the two lower tanks. Are you saying that it can be removed without separating the hose from the right radiator? I thought it might be possible, but I haven't tried yet.

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Now Now Cruzr944, slamming the lesser tradesmen is like slamming the riders of the not blue bikes, It is such an easy and unrewarding sport. Much like shooting goldfish in a bowl. Have a great day. :cry:

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On my '01, the shaft, which looks to be a good 1 1/4" long is about 1/2" away from, and perfectly lined up with the crossover between the two lower tanks. Are you saying that it can be removed without separating the hose from the right radiator? I thought it might be possible, but I haven't tried yet.

I don't actually remember exactly what I had to do to remove it. But I know for sure I did not have to drain the coolant. You may have to loosen and "jimmy" some things around but you shouldn't have to separate the rads. Although that might be "easier."

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