Why am I dumb? and other tuning questions

[moosehead]

Rejetted the carb couple of weeks ago. Shortly thereafter the bike developed and intermittent bogging problem under wot load.
Thought my bogging problem was possibly siezing due to lack of oil. Premixed a little and fouled the plug. Dumb
Tried the 19mm Arreche to see if that would help. Of course without a 70cc kit and pipe, it was too rich and did the same thing. Dumb
Added technigas pipe hoping that this would lean it out a little. Of course without clutch springs it can't even get on the pipe. More dumb

So why didn't I listen to good advice and just lean out the stock carb? Cause I am dumb. Being an engineer, I thought too much instead of going for the simple fix.
So I changed out all the gas after I found the oil injector works fine and reinstalled the stock carb. Left the technigas pipe on. It runs well and doesn't bog down. Still can't get on the pipe till I change the clutch springs, tho.

Changed the variator with some aftermarket job from ebay. It fits with only minor modifications, which leads me to believe that any Jog variator will fit with the same modification (beveled a little of the nubs that the v-bushings slide on.) I say Jog, because that is stamped into the factory ramp plate. I wanted to try this with a cheapie in case I flubbud it up, but it works fine. Unfortunately, it came with something like 8.5g weights. The factory variator weights are like 5g each. So, I ran half the aftermarket rollers. It doesn't accelerate very well with that pipe and these rollers, tho. Couldn't get much into the top end without clutch springs to test that. As these are the only 2 sets of rollers I have right now, what about running 15g total weight (top speed is not a concern right now) or shoud I just throw the stock pipe back on until I can get some clutch springs and a roller kit?

[Zuma-Zuma]

This is why Provo, and others, have ENGINEERED stages. They are matched, and proven to work with minor fine tuning to get it near perfect. You can look at some of the staged kits, and find out where you may be lacking. Variators should slide on, no mods needed. It sounds like its just wrong. You need good parts, made for your scooter, that are proven to work together...you have to many variables.

But yes, clutch springs sound like a major hurdle for you right now.....

[XPS1210]

nicely said zuma-zuma

[Zuma_Man]

can I have your 8.5g rollers?, I am having problems with my stage 1, though I need some fine tuning, but at this rate I may need 16g rollers, lol :)

[Zuma_Man]

hey jered, just wondering, why was my message deleted?

[XPS1210]

because the post above yours that was deleted... I simply deleted both to eliminate any issues from the other post...

if you want you can repost the info that didn't pertain to the other post...

[Zuma_Man]

I only posted mine because it related to the other, I posted it to balance it out, but deleting both can balance it out.

[ratboycom]

well, if you look at the provo sales site he says that the techno had to be modified to fit tng and vento cranks, so there is not a ready made vari for our bikes (mainly due to the bigger crank, but.... if you got a performance crank that would fit you could run more comon vari's)

[moosehead]

Yup, that's why I had to mod the vari. It worked, but I still need to do some roller tuning today. I actually often enjoy engineering my own solutions rather than taking those prsented to me in pre-packaged form. It may take longer to wrangle the parts and require more tuning (especially if no one here has a similar setup) but I appreciate the learning experience even if it is sometimes frustrating. Life's a journey. Taking a different path can lead you to interesting places. My destination may be stage 1.5 or so, but I may not get there by taking the same interstate as everyone else.

Don't worry about the deleted posts, zuma_man, everything's cool.

[XPS1210]

you were nice here... and don't need to delete the post...

with that being said, I probably will go to a stage .5, with installing an airsal cylinder only....

[moosehead]

I carefully scrutinized my post first!

Originally, I was going to do this (with a cast cylinder), but I ended up with enough stuff for more. Basically, stock is never good enough. I know you went back to stock, but once bitten by the speed bug, you are infected for life.

[Zuma_Man]

thats cool man, I'm glad we're cool, I wasn't, I wasn't trying to offend you. I dont think I'd go with cast cylinder, if you read cast iron vs aluminum, it talks about how its temper treated stuff, and you can google that material used on the cylinder. Now it doesn't mean I'll be buying an airsal, I want to get a polini evo

[moosehead]

Well, I am also a BMW mechanic. A few years back, every BMW V8 built with Nikasil cylinders needed a motor (sometimes 2.) They switched to Alusil and the problem went away. I am not exactly a nikasil convert. Most motorcycles still use cast cylinder liners, and the longest lived engines that I work on are cast iron blocks with aluminum heads.

[Sonny]

Moose, I am also a tweaker like you, don't feel dumb, it's how you learn.
Don't count on JOG printed on the variator referring to the make of bike it's intended for. Believe it or not, I see the letters JOG printed on a lot of parts around. Quite often I see that on Honda Variators and some other parts. Have no idea what it stands for though otherwise...
If you put on a 19mm carb, that doesn't make it automatically too rich, sometimes you may be too lean instead, just depends on what the stock main jet is.

EDIT
From what I know, cast iron spreads heat more evenly accross the cylinder, minimizing hot spots. I really like aluminum more though, simply because it's easier to port and polish.
Aluminum cools off quicker, but it heats up quicker too, If I was to do short rides daily (oops, I do), I'd stay with cast iron.

[moosehead]

That's the other thing. My wife rides 2 miles to work. She doesn't want to warm it up longer than ride it. I think that the 19mm carb with the 95 main was too rich, and I can't get jets on a weekend (and I can't tune it on a weekday.) With the right tool, cast iron is simple to port. It may take longer, but it is more forgiving if the dremel gets away from you.
As for the Jog thing, that's interesting. My other clue, tho, is that Speedy_scooter said that his Vento has a Jog90 drivetrain, and supposedly Vento and Venice use the same stuff.

[Sonny]

Hey, guess I better validate myself before I go running off at the mouth huh?
I'm a scooter mechanic in Key West Fl. I specilaize in Venices, Ventos, Hyosungs, Daelims and Hondas. Those are the ones I work on daily, but I work on all makes and models.
I am a transplant from the pocketbike buisness, I used to own and I was affiliated with and several other minimoto shops.
Ok, that said, let me reply to your post...
The newer model TnG Venices come with a 16mm carb and a 94 jet, I can tell you that they are too rich out of the box, so a 95 with a 19mm should be about right. BUT, there are so many other variables involved.

I have been porting cast iron jugs with no issues, but my bits are more expensive than if I was poting aluminum. It's also a bit harder to get clean port walls with C/Iron. I can't just stick some sandpaper in the ports to smooth them out. Oh, and enlarging the exhaust port takes quite some time!

I'm sure you're right about the Jog thing. I know a ton of this stuff is interchangeable. Just about anything with a Minarelli style motor is interchangeable to some degree.

You guys will probably see me quite a bit around here, I'm a scooter junkie and even though there are TONS of scooters down here, there aren't that many scooter "hackers" for me to play with!

[moosehead]

How new? My 2004 came with a fairly small Mikuni carb and a 70 jet. BTW is that Spike?

[Sonny]

You bet that's spike! Good eye!
You know, I'm not sure how new, I never cared to check the Mfg. dates. The "standard" Venice does come with a Mikuni (and some clones) with 70 jets, those carbs are superior than the other with the 94 jet. Before I got to the shop the other mechanic was taking the 94 carbs off the newer bikes and replacing them with the older Mikuni models. Kind of a waste considering all he had to do was change the jet that was already in the bike.
The other carb is a clone and although they look like the Mikunis you get used to recognizing the difference. Is your wife's a TNG, the 50q (whatever it's called) or just a straight Venice? Does it have a disk or drum brake up front?
If you have any specific questions, I have about 20 Venice's sitting around the shop, I'll get you info. at work tomorrow.
BTW, for all Venice owners; these are decent bikes, I have some with over 7000km on them that still run pretty strong. Yeah the plastics suck and they have a few other issues, but they are actually pretty well respected down here.