Stupid flat spot...

[functioning_on_impatience]

After nearly 2 months out of commission, my '92 GS is finally coming back to life.  Clutch cable replaced (just finished and hour ago), new battery (charging as I type).  Just silly stuff that I didn't have the time to fix...figures I fix it as the riding season is winding down.

Back to the problem I had before the clutch cable broke.  My bike has a rather substantial flat spot between 6k-8k revs.  It pulls strong right up to 6k, and from 8k to the red line, but nothing in between.  I have a high flow air filter (read: stock air box is completely gone) and stock exhaust.  Is it not getting enough compression?  Is it the carbs?  I don't know.  

Any ideas??

(Actually it wouldn't bother me that much, but it makes merging onto the freeway kinda scary.)

[Jace009]

how do the plugs look?  I'm concluding that the mixture is a little off...there is defently a flap spot about about 7.5k but yours is comming on much sooner...Sounds like it's extra lean. Do you know what size jets are in it?

[functioning_on_impatience]

As far as I know the jets are stock.  I've never messed with them, but the guy who had it before me did a lot of stuff.  Might they just need a cleaning?

[sprint_9]

The K&N flows way more air then the stock unit and rejetting is necessary if you want the bike to run right.  I have read that with the stock pipe it is very hard if not imposible to get the mixture just right, you may consider an aftermarket pipe or maybe even drilling your stock eshaust out.  Could need cleaning but I would bet that some jetting is necessary.

[The Buddha]

Pretty much what sprint_9 said... pipe/slipon may be needed and then 40pilots 150 mains and 1 washer under needle and air screws to 3 turns... then post back if your bike dont run like a steroid hopped up race horse...
Cool.
Srinath.

[functioning_on_impatience]

a-ha!  I'm an idiot.  I failed to mention that the bike tries to stall during idle sometimes.   I forgot it was doing that until I fired it up the other night.  So basically, the bike is getting too much air and not enough gas.  

*Sigh*  I just pulled off the crappy homemade high flow exhaust the previous owner had made and put the stock one back on...  Does anyone have a cheap slip on and a saw-zaw I can borrow?

Srinath, you lost me with the specs there... Is a Stage 1 kit going to do it?  How much is one of those things going to cost anyway?

[The Buddha]

Do not buy a jet kit. If you must spend $$$ send me $40 and I'll jet it for you, parts and labor included. The jets I was saying are like a stage 3, but individual jets from mikuni and stock needles work 1000 times better. 40 non bleed pilots Tucker Rocky part number 42-7130, 150 large mikuni slotted round mains, and #4 washers under the needle 1 each... If you want these parts I'll sell them to you as well... ~$15-16 plus shipping. But... jet kits suck... drilling out your slides ... huge no no...
Cool.
Srinath.