Author Topic: My first problem!! Aaaawwwww how cute! (Read 5380 times)

jeepskate99 · « **on:** July 22, 2006, 10:32:07 AM »

Ok. I will talk to my normal guy tomorrow but I want your opinions. Here we go.
2004 B12S

Yosh slip on
Ivan's Jet kit
Idle screws 3.5 out (I believe)
Stock ignition timing
Air box drilled
TPS=piece of shit on order (many said this won't be it)

The bike has a bad (to me) lag off idle. Taking off from a light requires more revs until the bike is above 2000-2500 rpms. Not the normal clutch dragging the engine down but more severe. Seems to runs strong through midrange and on up. CANNOT WHEELIE FOR IT'S LIFE!! That can't be right since in stock crappy form it would loft the front like nobodies business.

Temp has been around 85-95 degrees F.

What do you all think the problem could be?

PaulVS · « **Reply #1 on:** July 22, 2006, 10:50:03 AM »

Sounds like it might be running a little rich. How is the powerband after you get the RPM's up?

You should find out what your A/F screws are set at. You could try to turn them in 1/2 turn.

If that doesn't do the trick, you may need to move the needles up a notch.

jeepskate99 · « **Reply #2 on:** July 22, 2006, 11:24:23 AM »

Seems good above 4k. Even lifted the front wheel under power in second once. Ok a slight pavement imperfection helped it out but still.

Also thanks for responding so fast. This same thread has been on Max-zuk for a day with NO answers.

PaulVS · « **Reply #3 on:** July 22, 2006, 12:02:46 PM »

Ooops.... I mis-typed. (Or a brain-fart, which I won't admit)

If adjusting the A/F screws doesn't help, you'll want to LOWER the needles, not raise them.

BTW... I have the exact same setup... '03 1200, Yosh RS-3, Ivan's jet kit.

I will say that with the jet kit the initial off-idle power might be down on mine vs. stock as well... but from 3000 RPM's on... it screams.

I think it's the trade off of jetting. Do you want to wheelie or do you want to rip-snort?

Still... you should be able to tune-out any serious bog with some adjustments.

jeepskate99 · « **Reply #4 on:** July 22, 2006, 01:12:28 PM »

Brought em in a half a turn each and then the rain came back. Will update later today if the weatherman is right.

2005B12S · « **Reply #5 on:** July 22, 2006, 01:27:48 PM »

First, to wheelie without any effort drop one tooth on the front sprocket. Regearing is the easiest and cheapest performance mod you can do.

As far as jetting, The 2G airbox sucks, its too small and restrictive. The 2G frame redesign restricted the volume of the airbox due to the revised frame downtubes.

I had the Ivan's kit (airbox mod, Yosh pipe) on my '05 and was never able to get the jetting spot-on. Your off idle stumble is in the mixture screw/pilot circuit range. 4 turns out was the best setting for me, it was OK but a 10-15 degree change in ambient temp would either cause a low speed stumble (too rich) or a slight backfire thru the carbs (too lean). I finally had enough and shucked the stock carbs and airbox.

If I was to do it again, I would go with the HS stage 2 kit and pods right from the start. I think getting rid of the airbox solves a lot of the problem and makes jetting easier and less sensative to temp changes.

Some guys are happy with the Ivan's kit , maybe I am just a perfectionist, but it was not a good enough setup for me.

Good Luck, Ed.

jeepskate99 · « **Reply #6 on:** July 22, 2006, 01:35:01 PM »

Quote from: 2005B12S

First, to wheelie without any effort drop one tooth on the front sprocket. Regearing is the easiest and cheapest performance mod you can do.

As far as jetting, The 2G airbox sucks, its too small and restrictive. The 2G frame redesign restricted the volume of the airbox due to the revised frame downtubes.

I had the Ivan's kit (airbox mod, Yosh pipe) on my '05 and was never able to get the jetting spot-on. Your off idle stumble is in the mixture screw/pilot circuit range. 4 turns out was the best setting for me, it was OK ....

Good Luck, Ed.

I was at 3.5 and judging by my tailpipe, i was WAY too rich. Of course it was last set when it would hit a high of 45 degrees during the afternoon.

2005B12S · « **Reply #7 on:** July 22, 2006, 01:35:19 PM »

Quote

I think it's the trade off of jetting. Do you want to wheelie or do you want to rip-snort?

A mostly stock, properly jetted bike should be able to do both well.

You should only have to start making sacrafices in power delivery when you start making extensive engine modifications - such as : high lift cams, porting, full exhaust, aftermarket (non CV) carbs ect.....

2005B12S · « **Reply #8 on:** July 22, 2006, 01:48:02 PM »

Quote

I was at 3.5 and judging by my tailpipe, i was WAY too rich. Of course it was last set when it would hit a high of 45 degrees during the afternoon.

If thats the case when the temps come up you will be even richer. Pipe color can be a good clue but plug readings are always the best indication. And sometimes an obvious stumble or backfire makes pulling the plugs unnecessary.

My bike would be fine at 85F but a 15 degree drop in temp would induce lean backfiring thru the carbs.

I never got a chance to try the stage 2 and pods but it has to be a better alternative for the stock CV carbs. IIRC, the stage 2 uses something like 150 mains and Ivan's kit uses like 110 mains. That shows how restrictive the airbox is. You should not have that large an increase in the mains buy just removing the airbox.

jeepskate99 · « **Reply #9 on:** July 22, 2006, 02:07:56 PM »

The plugs indicate good but there is a problem with that. I don't commute with my bike so it doesn't spend much time under 3k rpm. The richness down low will not show on the plugs when the engine was run higher. I could just let it sit and idle for 5 or so and then check though. But the exhaust gas analyzer from work looks like its bad down low too. One of the techs brought it over a few minutes ago and we did some playing in the garage.

jeepskate99 · « **Reply #10 on:** July 22, 2006, 06:16:23 PM »

Took it out for around 5 miles between rain showers after warming in the garage. 1/2 turn in on each screw (which were at 3.5 out).

paul!!

PaulVS · « **Reply #11 on:** July 22, 2006, 07:39:23 PM »

So you're at 3 turns now and it runs better?

jeepskate99 · « **Reply #12 on:** July 22, 2006, 07:47:13 PM »

Quote from: PaulVS

So you're at 3 turns now and it runs better?

much better. I may play with it some more on a better day where I can est more often. Or I may take it to a friend of a friends shop and use the dyno to really do it.

2005B12S · « **Reply #13 on:** July 22, 2006, 10:11:36 PM »

Quote

The plugs indicate good but there is a problem with that. I don't commute with my bike so it doesn't spend much time under 3k rpm. The richness down low will not show on the plugs when the engine was run higher. I could just let it sit and idle for 5 or so and then check though. But the exhaust gas analyzer from work looks like its bad down low too. One of the techs brought it over a few minutes ago and we did some playing in the garage.

That is a hard read, but looks like you have made progress. Be prepared to richen it back up when temps change in a month or two.

Enjoy, Ed.

2005B12S · « **Reply #14 on:** July 22, 2006, 10:13:45 PM »

Quote

So you're at 3 turns now and it runs better?

If only I could figure out how to load photos like that!

My vote is for the hottie on the far left