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BB/FCR/Hot cams installed -- slight issues

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We did the '50hp kit' by Eddie yesterday and got it up and running. The FCR came tuned for this set up, supposedly, but we're having some issues keeping it going. It doesn't want to stay idling unless the idle is adjusted to ~3-4k, there is some surging at steady throttle, and the bike seems to be getting extremely hot (yoshi titanium now glows red within a minute of idle), the fan kicked on...

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Vacuum line connected? New FCR from Eddie? Confirmed the fuel screw was opened? No vacuum leaks?

Bike sitting in one place for minutes at a time idling/running will make the bike over heat, the header glow if there is not air flow. Get a big Box fan, that will help.

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got the vacuum line connected to the petcock? carb all the way in the manifold? 100% sure cam timing is right?

your carb set up is the same as hundreds of other drz's.

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Would not installing the vacuum port nipple cause these issues? #13685-29F00

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Would not installing the vacuum port nipple cause these issues? #13685-29F00

If the vacuum port is not capped off one way or another the engine will be sucking in air causing a lean running condition, which would explain all your symptoms.

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Just looked through all of my boxes and didn't find the port nipple. Hmm? Should have been supplied...

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Easy to make for purposes of testing. Piece of hose with a bolt or the like pushed in one end then pushed over the vacuum port to cap it off. Test it with that to see how it runs.

If it's ok then get a cap/something more permanent. :bonk:

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So the nipple was actually installed on the bottom 14mm and it is connected. I must have missed when my buddy put it on.

I went ahead and threw a zip tie around the nipple and started it up. It idled fine, not a consistent idle, but an up-down (hard to explain). I still need to take it for a ride to see if the surge is still there. Other than that, it still seems to be getting excessively hot. Is that just a symptom of a big bore/fcr/cams? If so, how am I going to deal with slow, off road riding?

Other than that, the little hole on the left side of the engine -- am I suppose to see it filled with oil?

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I suspect you still have some sort of vacuum leak. Not uncommon for that little vacuum hose to get split. The idle you describe is also called a 'wandering idle'. Cause is a slight lean condition, hence the concern about a vacuum leak. Did you adjust the fuel screw at all?

What 'little hole' on the left side? There are none other than the stator cover, they are caps/covers/plugs that go in them.

As far as the heating goes, I doubt the engine is getting hotter than normal. The exhaust might seem like it due to it being thinner wall tubing. As long as your speed is at least 15 MPH, your cooling fan should never come on and that confirms you are staying nce and cool.

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I haven't touched the fuel screw. I'm just not sure where I could be having a vacuum leak. Any ideas?

The tiny pen head sized hole that's on the valve case. Above the timing sight hole.

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im thinking the little hole your trying to us is the drain hole for the sparkplug well.if your leaking oil out of that then your valve cover gasket is probally not sealing at the sparkplug hole.

as for your lean condition i would start up the bike and spray some wd40 around the carb boots and vacume lines to see if there is a difference in the idle.if there is then you have a vacume leak

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Tried WD40 at all of the hoses and didn't notice anything.

it's still dying down at low idle. I'm lost. It could still very well be a vacuum that I'm missing...?

I did notice that the line going from the little black box (oil/emissions crap) to the top of the air box boot is slightly bound up. Could this be causing it? ETA: I unplugged it from the air boot and straightened it out. nothing changed.

Edited by teedubb

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OK, more fishing around. Is the 'wandering idle' normal during warm up?

I was able to get it running without dying on me, but no matter what I did the idle kept jumping around. I kept adjusting the knob and it was either too low or too high, no in-between...

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it normal to need to use the throttle to keep the bike runnign during warm up. you set the idle speed with the motor at full temp.

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it normal to need to use the throttle to keep the bike runnign during warm up. you set the idle speed with the motor at full temp.

+1 on that

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im thinking the little hole your trying to us is the drain hole for the sparkplug well.if your leaking oil out of that then your valve cover gasket is probally not sealing at the sparkplug hole.

:bonk::thumbsup::smirk:

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Tried WD40 at all of the hoses and didn't notice anything.

it's still dying down at low idle. I'm lost. It could still very well be a vacuum that I'm missing...?

I did notice that the line going from the little black box (oil/emissions crap) to the top of the air box boot is slightly bound up. Could this be causing it? ETA: I unplugged it from the air boot and straightened it out. nothing changed.

its starting to sound like your pilot jet(inside the carb)could be partially obstructed

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Idling seems to be worked out now...for the most part. Took the bike for a 3 mile ride and it ran like a champ minus a stall as I was leaving the garage.

When I got back, I had a line of oil coming out of that hole that I was talking about (referenced with this random picture: http://www.dirtbikeworld.net/Reviews/Suzuki/DRZ400/Left_Engine_Big.jpg)

How does the valve cover gasket effect that hole?

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