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Dying on blip

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New thread.

Bike with complete 50hp kit. Was running fine, but had a wandering idle. Changed needle to a thicker one, and at 2 turns out. This is where the problem started. When I give the bike a very quick twist/blip (and let go), the bike dies. When riding the bike, at full throttle, it is bogged down severely with a loss of power, but won't die under constant throttle.

I am at a complete loss. Eddie and I have been back and forth and I am just running out of ideas. The new needle is not the cause of the problem.

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Check the airbox adapter for an airleak. Mine was loose and caused that once. I tightened up the adapter and the idle stabilized and the surging went away. I also did away with the wired AP linkage at the same time I did the repair. Much better now.

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The needle has nothing to do with idling. I'd go back to the old needle and try and fix the idling problem.

It is normal on an FCR carb for the motor to die or stumble when you whack the throttle in neutral.

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I dare to say there is no one more educated than Eddie in regards to drz tuning and trouble shooting....

If you purchased the kit from the Master I would continue direct correspondence with him to sort it out....

I can't see how removal of the AP wire is going to be a remedy for riding at full throttle.....

What main jet is installed?..It should be a #155..

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The needle has nothing to do with idling.

not really true. the root diameter of the needle influences the idle circuit.

teedub you to check to see if the main jet is laying in the inspection cap.

do not remove the wire.

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Where's the inspection cap on this carb?

I pulled the spark plug (should have done it to begin with) and it was black. Which points to running rich. Before the install of all the new components it was a light chocolate. I'm about to replace it now.

Bobbed, the boot fitting is a huge PITA! It was my first concern, but it should be OK.

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main jet looks good...

i rode the bike today. did a little off roading (this is a supermoto) and killed the bike a couple of times (to stop for a break, and stalled once). Both times the bike was a little difficult to get back started -- as in, it took two or three pushes on the start button to get it going.

after the ride (30 miles, some high speed pulls), i pulled the NEW spark plug to check its condition, and it had a egg shell colored white square on the tip. Lean or normal? Should be more brown, I thought.

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spark plug color means nothing with modern fuel.

im confused. you say it wont even hardly run at open throttle but you are out off roading it?

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it is bogged down in gear under full throttle, but will still run. it idles fine as well. the biggest thing i'm having an issue with is it dying or being unresponsive under blips in neutral. and the newest problem -- it not starting on the first try after being ridden for awhile.

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what it does in nuetral is irrelevant. you dont ride in nuetral.

so if you hold the button down it wont start? it just cranks away for several seconds then you repeat this 2 more times?

if its having major power out put issues you need to stop riding it. pull the valve cover and take pictures of the cam timing marlks and the tdc mark line up in the hole.

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so if you hold the button down it wont start? it just cranks away for several seconds then you repeat this 2 more times?

Exactly. Which is odd since it usually starts pretty dang quick when cold.

I'll get pictures.

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Eddie, I just pulled the valve cover and rotated to TDC via 5th gear wheel turning (didn't have a big enough alan to remove the side cover), and the lobes are pointed inwards (5 and 7 o clock). I don't understand how that could happen...we triple checked the timing...so, unless we did something wrong or i did something wrong in rotating to TDC.

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I notice the marker isn't between 14 and 15, but after 15.

And here's a couple of videos from todays ride. One showing the starting, another showing WOT (with short shifts). If you think the timing looks fine, and the bike seems to be running fine, Eddie, then maybe it's all just in my head and I'm just not accustomed to the new set up.

http://youtu.be/jodmPLli8RU

http://youtu.be/sxGJO-iunss

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the gasket needs to be out of the way.

i see nothing wrong with the starting other than you stabbing at the button instead of just pushing it till it starts.

the video shows fine throttle response and fine wot throttle running.

im really confused as to what the issue is.

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then maybe it's all just in my head and I'm just not accustomed to the new set up.

I agree...It looked like business as usual on the vid..:smirk:

As Eddie said ,that cover gasket is blocking view of the marks on the cam sprockets....

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Sorry, there's a little bit of gasket maker on the inside and I didn't want to risk tearing the gasket.

ev6h45.jpg

If ya'll think the timing looks good, then the bike is back together. It could be that the FCR/engine set up makes the bike a little more finicky than what I am used to in stock form.

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