PHBG Tuning - Garelli VIP

ok folks, I got some questions, setup first, questions second.

Garelli VIP 2 speed

64cc polini

20mm polini intake (necks to 17mm on carb side)

Leo Franconi circuit pipe

75w90 in tranny

150lbs compression

B7HS

Avanti CDI, factory timing

21mm PHBG

#50 idle

#60 pilot

#90 main

w7 needle, 2nd notch from the top

#40 throttle cutaway

#262AU emulsion

*no filter

Alright, so heres the deal. Bike runs great and starts easy on the stand, need the choke when cold, but that's normal. Operation is normal until it heats up, runs well. After about a mile though, the trouble begins. 1st speed is fine, run through it, plenty of power, shifts late, on purpose, the heavy fluid. Once it shifts into 2nd, it lags through the whole throttle. If I dump it down to about 1/8th throttle and slowly work it back up, it'll pick up, but slowly.

Main jet wise, I've tried super huge jets, dangerously small jets, and everything inbetween, combos with a filter and without, and different filters. The only other idle jet I've got is a #45, it doesn't do any different. Needle position seems to make it worse if I raise (richen) the needle, but the top position seems no different than the 2nd.

It's been suggested to me that heat fade might be my issue, but I'm running a B7 for a long time, with various carbs. Most recently, with a 19mm SHB, and it did fine.

I read in the wiki on this page that throttle slide cutaway is important in multi speed bikes, and that it is particularly important for the 1st half throttle. Could this be my problem?

How about that needle? what about the W7? it seems to be rich, but I've been wrong before.

The plugs come out oily, but when wiped clean they are coloured correctly. I'm assuming the oil is coming from low rpm stuff, idling, slowing, etc. rich? wtf. this carb might kill me.

Later tonight, I'm going to put everything as close to stock as a kit/pipe/carb will allow and give it another go.

so, advice? I'm lookin' at you, Garelli people.

Re: PHBG Tuning - Garelli VIP

Strange that it's happening right after you shift into second. You don't think that your motor can't handle the low RPMs of the second gear in combo with that oil, do you? That kind of sounds similar to when I was screwing around with 18 tooth front sprockets with mine. Once it hit second (after taking forever to get into it), it was just too much for that motor to pull. Also... it could be combined with you being overjetted. I have almost the same set-up and I've done fine with a Uni filter and a 78-76 jet. What's your gearing?

Re: PHBG Tuning - Garelli VIP

gearing is 17-24. Martin had a similar problem, he leaned out his middle a lot and it kinda fixed it. definitely need to go back to solid weight 30 until I figure this out.

Re: PHBG Tuning - Garelli VIP

swapping the trans fluid helped some, 10w40 now, but same problem persists.

Re: PHBG Tuning - Garelli VIP

It must be the gearing. Does it still take forever to shift into second? I'm figuring when it shifts into second, your RPMs drop way low. Just like when you shift into 2nd gear too early while driving a car, your car bogs for a while until it gets the rpms up enough to push the vehicle. I don't know... just a theory. Downjet!

Re: PHBG Tuning - Garelli VIP

I have a 16 pinion I can try. I'll look into it.

Re: PHBG Tuning - Garelli VIP

no filter at all? any tube or anything before?

shit i dont know, id almost think that idle jet was kinda big but sweet jesus dont go running a 38 cause i said it haha.

especially since raising that needle made it run better.

Air leaks anywhere? Why is that plug oily?

does a wide open plug chop tell you you are the right area for your main?

god learning a big del can be tough. Im glad i didnt try on a 2 speed.

Good luck man.

HOw long this been running? You way past break in?

Re: PHBG Tuning - Garelli VIP

No filter, living on the edge.

I've got a #45 idle, maybe I'll give that another, more indepth try.

No air leaks. Oily plug seems to be the result of low rpm running.

wide open looks good, 87-90 seems to be my proper range. of course, you have to wipe the low rpm oily off before you can read it. there is no way I'm getting rich/oily plugs out of a 87 at top speed, so it must be from lower down the range.

break in was done a long time ago. I run in hard, 50:1 dino oil, doesn't take very long.

I can't get past this notion that I need a different needle...

Re: PHBG Tuning - Garelli VIP

well, shit, it is a really cheap option LOL

Needles are cheap.

Where did you find a kit for a vip?

super curious on that. I have a gulp.

Id be scared shitless to kit it with that rubber band tranny o mine, and cause i absolutuley LOVE my gulp....

but i like kits too...maybe just with a 16mm del lol

is it reed?

Re: PHBG Tuning - Garelli VIP

Angelo has the 46mm polini kits for $260 shipped I think.

Anyone know somewhere to get them for cheaper?

Re: PHBG Tuning - Garelli VIP

I bought my polini 64cc used from a guy who put like 6 miles on it. I have no idea where he got it. ebay.it, maybe?

Re: PHBG Tuning - Garelli VIP

Yeah, try out the 16. I need to get my 24 tooth back on. The sucker shifts waaaay too early with stock gearing. I think I'm going to do up that cylinder this weekend. I'll let you know what happens, Zack.

As for kits, I have a couple I may be willing to part with.

Re: PHBG Tuning - Garelli VIP

Yeah, Italian E-bay. They pop up a couple times a month. Just gotta keep checking.

Re: PHBG Tuning - Garelli VIP

hmm. Interesting

If anyone ever has a decent spare bottom email me.

Mine has some rod knock going on that scares me.

Re: PHBG Tuning - Garelli VIP

I have a similar problem with mine, it seems to shift too early, about 20 mph, then from 20 to 25 its a dog but aftet that I have plenty of power.

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