Wideband o2 sensor to tune scooter

[LMH]

What set up are you using a 50 and 55 pilot on? If its the corsa with the 24mm theres an air leak somewhere for certain. On both my 24mm oko and corsa Af16 and Af18 I run Ct chromes 45 pilot and 132-135 mains 1 5/8 turns out, needle in 2nd from top spot, with a motorio expansion and a PG long. Never hit over 1000 degrees F and maintained 850-920 F ish entire rpm range all the way to a little over 11k. Meaning stoich almost the entire time. Hottest time is always when letting off the throttle.
Both cases have been extremely ported and so has the intakes.

[Chicago Ben]

I run a 52 pilot on a 50mm ruima bore, 28mm keihin, ct mani...

[steffen707]

I'm at needle clip at the top, it runs great but not at low throttle, I'm going to lower the clip and the pilot. I tried spraying carb cleaner all over the intake but didn't notice an idle change. I'll try that again tonight.

[steffen707]

Here are some pics of the o2 setup. I used a cigarette lighter splitter for the connection, its nice because it has a fuse build in, so I don't have to worry about the gauge. I tapped into 2 wires at the key switch for switched power and ground. My buddy did the welding. I think it looks nice, not his best, but looks like dimes laying on each other.

[steffen707]

Well how about that, I sprayed a ton of carb cleaner on the rubber boot and 2 hose clamps and it started idling rough and eventually shut off. So I cranked on the hose clamps and busted one, bought 4 new ones. Took the rubber coupler off dried off the inside, put 2 new hose clamps on,cranked those down, and when you spray carb cleaner on it, the same thing happens. I did have to spray a ton before this happened, but I'm assuming any change in idle is bad right?

Do I need a tighter coupler, stronger hose clamps? Ugh!

[steffen707]

I was reading on another forum that somebody else had trouble with a rubber intake/carb spigot and just used rubber heater hose in place and it sealed up nicely for them. Anybody try that before? I think i'm going to give that a shot.

I've never had a leaky radiator or heater hose before and that's under like 12psi.

[Trafficjamz]

Well how about that, I sprayed a ton of carb cleaner on the rubber boot and 2 hose clamps and it started idling rough and eventually shut off. So I cranked on the hose clamps and busted one, bought 4 new ones. Took the rubber coupler off dried off the inside, put 2 new hose clamps on,cranked those down, and when you spray carb cleaner on it, the same thing happens. I did have to spray a ton before this happened, but I'm assuming any change in idle is bad right?

Do I need a tighter coupler, stronger hose clamps? Ugh!

Maybe the gaskets on the ct are leaking, and not the boot?

[steffen707]

When I sprayed the intake it didn't change idle, when I pulled the rubber spigot off there was carb cleaner puddled inside it.

[steffen707]

So i'm pretty sure the gaskets on the CT intake aren't leaking, but I know for sure the rubber spigot is because of the carb cleaner inside of it.

I'm going to try some radiator hose hopefully tomorrow and seal up that leak and then test for any more leaks before I rejet.

By the way, i'm doing all this leak testing and jet changing without the wideband installed and just an o2 plug to increase the life of the sensor, once I think I got it where i want it, i'll test one last time with the wideband. I have it installed in a way that In a matter of 10-15 minutes I can throw it back on the scooter to test when it gets colder out.

[steffen707]

Okay got a 1.25 inch piece of radiator hose tightened that down and it'll still die when spraying carb cleaner. So I got to thinking maybe it's coming in from the choke? I pulled the choke out and the bottom definitely smells like carb cleaner. Anybody ever have an air leak from the choke before?

I'm off to the store to buy a bolt to seal off the choke and then try the carb cleaner again. This is * me off.

[steffen707]

I've finally stopped the intake leak. I re-jetted the pilot to a 50 and seem to have highest idle at 1.5 turns out from fully closed. I seem to have an overly rich situation at 6000rpm where I get about a 11.4:1 AFR. This usually happens around 1/2 throttle, if I open the throttle more it bogs for a second and then when the rpm jumps from 6000-6500 the rich situation disappears, it goes up to about 13.2AFR, and then screams at WOT around 12.5-13AFR until I let off.

I was at about a 13-13.5AFR at a 120 main, so i dropped down to the 118main, that lowered the AFR to the 12.5-13 but didn't cure my overly rich 6000pm area. Before when I had the needle at the top clip I didn't seem to have this bogging at 6000rpm, but then i was getting far too lean at 1/4 throttle. I'm thinking I might need to look at the taper of the needle.

I remember Bakaracer suggesting I also need to screw with the trans, maybe i'll start playing around with that next. Only so much time in the day.

[fastplastic]

Not sure if u knew this or not but the pg long does have a weird bog like situation on the bottom side of things.... Traffic and wheels could probably describe it better u might need a video to get more specific help as well

[steffen707]

Thanks fastplastic I had no idea about this bog situation.
I'll do some searching tomorrow to find some info.

[kingkamehameha]

Pg long is a real easy pipe to tune. You need weights that are 7.5 8.5 9.5 etc. I think wheelman has sanded weights down for the same desired effect. Your weights and spring combo will cure that bog as well as a nice carb tune. Sym makes some excellent weights that last a long time and they come in those X.5 numbers. Sos also makes good weights. Rider ad bike weight are also variables. What works for others may not be suitable for you. Also riding style has a big influence on your trans set up and gearing.

[steffen707]

I finally understand what was meant that the trans and carb need to be tuned together.

I'm going to post this in the other thread I started about more of the tune as well. To some of you guys this will probably sound stupid and elementary, but IÔÇÖm hoping somebody like myself that reads this post in the future can save some headaches.

I was having 1/8-1/4 lean condition as well as a rich bog issue around 6000rpm. I was kinda chasing my tail with making one thing better but screwing up another at the same time.

I read something on another site and it dawned on me, with the PG long I wasnÔÇÖt making any power under 6000rpm, so with the advice from lots of you I finally tried tuning the trans. I ended up breaking the clutch springs that I had on the scooter from before because I couldnÔÇÖt get them off. I put on some (what I think are 2k) clutch springs. My fianc├® doesnÔÇÖt know where her kitchen gram scale is, so I left the roller weights in and took the scoot for another ride.
Now the clutch engages right around 6000-6500, and I donÔÇÖt have the wussy no power lean situation I was getting when it was engaging at like 3500rpm. Also the bog issue around 6,000 is almost eliminated. The scooter is driveable and fun. I need to tune the roller weights and possibly change the 1500 contra/center spring so I get into the 8500+ power range because thatÔÇÖs when its really hauling.

So the moral of my tuning dilemma is that, I should have gotten the carb to run decent, then tune the trans to the desired powerband, and then go back and fine tune the carb if needed.
Thanks to all of you that have given me tips and advice. This scooter is so much fun now, and its not even fully tuned up.