Posted this in 4 stroke tech section too

[lauruven]

I'm a girl and although I have some knowledge of engines & carbs & workings of them & on them my knowledge is limited. So you may have to dumb it down. So a few months ago I purchased a 2021 wolf blaze scooter from someone I kinda know. The guy told me he had made scooter a 100cc, reflecting back I think this guy is more of a scooter hack then a self proclaimed scooter know it all. I met him on a referral thru advanced auto when I was having trouble with my previous scooter. Which he never did fix. So anyway come to find out his claim to it being 100cc on the scooter I recently bought from him was because he purchased a bbk (surely thru amazon) & replaced carb so it's bigger then the stock one it came with, muffler, & spark plug cable. He claimed scooter went 50-60mph easily. Which I found out after purchasing was a lie. It doesn't get above 45 on straightaway. I'd like if I could get it to go at least 5-10mph faster. What can I do? Now also here are some things I've done already and some issues I'm having.
THINGS IVE DONE: replaced cdi, voltage regulator, & spark plug cable. Took carb apart to check bowl & cleaned only 1 of the jets don't ask why I didn't clean other 1 I don't know. I'm nervous messing with carb because last scooter I feel I messed around with carb and it never ran right again. Maybe fluke why it never ran right again or fact that it was a 91 pos yamaha razz with multiple issues but I always attributed it to me messing with carb.
ISSUES: Difficult to start from cold start & will idle lower & lower til stalls unless I keep on throttle. Once warmed up it idles fine for most part and won't stall & will start right up if shut off. Sometimes after riding extended period of time it will idle rough like it will idle slightly higher then back down to normal & when it does this the scoot shakes slightly. Should I replace starter or something else? Also when on throttle going downhill or when fully open on throttle for extended period of time it will backfire a little & on a few occasions it what I would call hiccuped before backfire on straight way while fully open. Which was a bit startling 1st time I encountered it to happen. Backfire isn't loud but I notice it. Guy told me he likes to run his carbs lean could this be causing that or something else? Please any and all advice would be greatly appreciated.
Also why can I never find this brand scooter when looking for parts? What is it called so I can look up parts and stuff for it?

[pili]

The issues cold and hot lead me to think it’s jetted rich, the cold enrichment magnifying the issue until it warms and the enrichment stopping, making it run better. Once a plug is fouled rich it will act funky. I would do plug chops, idle, partial and full throttle runs of at least 30-45 seconds, using the kill switch to stop the engine and check the plug. Change to a new plug between runs.

Somebody more experienced can help you find parts.

[lauruven]

What are plug chops?

[lauruven]

Change spark plug?

[lauruven]

I don't have anyone with more experience to help me. That's why I'm here to learn to do things myself. Also if it's too rich then I would wanna turn down the fuel on the carb? Do I do anything with the air screw? Like I said you may have to dumb it down for me a bit til I get the hang of it more and am able to use correct terminology of things.

[pili]

May 30, 2024 8:02:26 GMT -5 lauruven said:

What are plug chops?

I'm sorry, I should have explained that the 30-45 second runs, ending with stopping the engine with the kill switch, are the plug chops. Basically it's looking at the spark plug to see how idle, partial and full throttle is affecting the plug. Good way of knowing if it's rich or lean. It's a good idea to change the plug in between if it's lean or rich (if the spark plug center and side electrodes are really light or white reflects lean, dark almost black is rich), so that the next test is on a clean slate. The air screw most like to start out about a turn and a half out from all the way in. As far as tuning, you can turn the screw out very slowly with it idling to fastest RPM and then about a quarter to a half turn back in.
None of us are born knowing this stuff, most of it is learn as we go, and this forum is a great source.

[lauruven]

Thanks I appreciate the clarification on that. I'm trying best I can to do any work or maintenance on it myself. The closest place to me charges $120/hr labor fee so I can see that adding up quickly. If things ever get too complicated for me I'll have to bring it to someone but for now things seem pretty manageable. My main concern is safety ecspecially cause on occasion my 10yr old daughter wants to go for a ride on it. And although I can't predict an accident I do everything possible to avoid one and am extra careful. So I wanna make sure nothing I could prevented caused a crash or any type of accident. It be really dumb of me to of known about a problem but ignore it for it only to later cause a problem 1 way or another. I do wish it were a little faster but I can't see how getting more than 5-10mph faster will be possible.

[\\-olf]

May 29, 2024 10:06:07 GMT -5 lauruven said:

I'm a girl and although I have some knowledge of engines & carbs & workings of them & on them my knowledge is limited. So you may have to dumb it down.

Good that you have the abilities to do your own work! be proud cause girls can do anything guys can with this kind of stuff- you just learn it like everyone else!

What you describe sounds like a big mess, some of this sounds like a hack job is behind it, and some of it is in my opinion- related to putting those ridiculous big bore kits on, seems like I see nothing but problems resulting, the rest of the engine was designed and made for 49 cc- including the connecting rod, you start increasing the forces and stress on that tiny connecting rod by DOUBLING the cylinder cc's you are begging for problems and if nothing else- early wearing out and failures.
I've always held that if a 49 cc isnt enough then buy a 150 cc bike factory made that way.

I can't really help your issues unfortunately, they sound like a multiple problem, if it was me, I would be inclined to just buy a 49cc crate engine, and swop out that "100cc" hack job and start over with a fresh unmessed with engine that isn't a "frankenmotor" and I have swopped engines before, it's real easy, hardest part is managing the bike's balance and weight while doing the work.

[\\-olf]

May 30, 2024 8:08:23 GMT -5 lauruven said:

I don't have anyone with more experience to help me. That's why I'm here to learn to do things myself.

There are some scooter repair books out there too, sometimes it's handy to be able to have a paper book you can read and refer to right there by the bike- the same kind of books exist as they do by Chilton etc who make automotive reair books, they will have pictures, definitions, terminology, how-to details etc- always good to use a variety of resources.