Hestitation when snapping the throttle open?

[cjard]

Hi Guys

Got nearly everything sorted on the bike that I wanted to with help from here, though one of the issues from before is still present.. I'm not sure if the tickover is a little low, have yet to check it, but i note if i snap the throttle open from idle, the bike coughs and hesitates. If it's doing somewhere above idle it seems fine.. Any typical problems that would lead to this?

Many thanks
CJ

[Mark Olson]

yes , put your idle at 1100rpm

adjust your air fuel mixtures with the blip test

synchronize all 4 carbs when the bike is at normal riding temperature.

and if you really want to get into it then check this out


http://www.factorypro.com/tech/carbtun.html

[markmartin]

What Mark O. said is a $$$-less option if you have the tools to synchronize. Dirty pilot jets would be my guess if a carb sync dosn't cure the problem. Clean them or, if they are stock size, replace them with 1 size larger than stock. I had this same issue and increased my pilot one size with good results.  Simply cleaning them may have solved my problem, but a larger pilot was suggested to me, and I went with that option.

[andyb]

Does it also do it when you're driving it?  Does it immediately pickup after it's coughed a bit?  Pilot circuit, synch, and/or fuel height would all be on the menu to look at, assuming that it otherwise runs well.  Could also consider bumping the timing forward, but that doesn't seem to be the primary issue.

[cjard]

Does it also do it when you're driving it?

I think so.. not actually tested as its a bit hard to get my  heavy ass rolling in any gear at tickover without stalling the bike, in order for me to test

  Does it immediately pickup after it's coughed a bit?

Seems to!

[weymouth399]

If it's the pilot jets you can turn the fuel enrichment/choke on a little bit if it starts to run better you have dirty pilots. It's that simple.
I have never seen anyone that took a bike from idle to rev all in one shot. You will never ride the bike like that so why is it so important that it does.
I set Idle on mine at around 950-1000 any more it don't start as well and I don't have the same comp brake at a higher rev. I love torque it works both ways on and off the gas.

Bob W

[JCainFJ]

Check the voltage to the ignition coils. If it is less then the voltage at the battery (it will be) install a power relay for the ignition. I had the same hesitation with my YZF and full power to the ignition coils fixed it.  I do this to all of my bikes, it helps them start better, I get a bit better gas milage, and my YZF made more power. I use 12 gauge wire for this and I also build a ground harness back to the battery negative terminal.

This is a link to Georges writeup about this.

http://www.wgcarbs.com/index.php?option=com_content&task=view&id=12&Itemid=26