2015 Super 8R NO POWER UPHILL

[dwbaily]

So I just got this scooter from someone with no history. From a friend of a friend. Just over 3500 miles on it. Found an online manual to try and learn what I can. See that it requires 92+ octane gas and not sure if previous rider used that so drained tank and put 93 in and a couple of ounces of Berrymans Chemtool in case of gum. When I ride it going up a semi steep hill, it slows down to like 5 mph especially when its cold outside. No experience with a scooter so not sure if a 49cc scooter does that with a 190 pound person on it or if there is something I need to troubleshoot.

It starts immediately. The idle is sorta smooth although it's sorta on the high side when I start it. Not sure if that's the choke, if it has one. On flat ground it actually accelerates pretty responsively and cruises smooth even though I've not taken it out on open road yet. Just rode in neighborhood. Not sure about top speed because the Speedo doesn't work. Ordered a sensor for down by the wheel. It's the electronic Speedo they switched to on the 2015 models. The 0 shows up and odometer but neither works when riding it. This thing HATES cold weather too! Was fairly cold this morning and I rode it after changing the spark plug and had to push it up short hill. Wouldn't pull me up it even after trying to get a running start at it a couple of times in my cul-de-sac.

Gonna take it to the local Kymco shop that is the only one I can find and hope they can check it over. Talked to the Kymco rep in Spartanburg, SC this afternoon and he said they come out of the crate restricted and that derestricting it would help. Whatever that means. Anyone have any suggestions/recommendations on what may be going on?  Thanks guys. 

[dwbaily]

Tore carb apart and sprayed everything down real good.  Seems to have smoothed out the idle but it still won't pull me up a not so steep hill.  Its like its either flooding out or the transmission is not fully engaging or something.  Bogs down.  Just on a hill.  So issues on flat ground.  Hmmm.......

[dwbaily]

So got it back from the shop.  Good news and not sure news.

So he replaced the big spring with a 1500rpm one and said that didn't do anything positive and felt all along it should have been a 1000 rpm one so he changed it to that.  Changed rollers to 3.5g rollers.  Changed the variator boss to a smooth one.  Adjusted the valves.  Removed the restriction washer from the intake tube.  Said compression is fine.  That's all he did.

Results:  A fair amount faster on flat ground.  Took it out on open road with my GPS and it got up to 40 best I could tell so that'll help when traveling in a 45 mph zone as long as a cop doesn't catch it in a radar.  32 mph is NC limit without a license.  I can tell it maintains its speed better uphill but still seems to slow to 15-20 mph which obviously beats 5-10 mph before I took it in.  Maybe that's to be expected being that I weigh 190 lbs.  Son weighs 165-170 so that ought to help some.  It for sure is better though climbing a hill than before.

The not so sure news is that the throttle is not smoothly responsive.  If I open it fully it doesn't bog down but doesn't max out like I expected it would.  Sorta gotta close the throttle a bit to get it to keep accelerating and then not see much difference in wide open throttle if that makes sense.  Was expecting the throttle to gradually increase the speed as I gradually open it on flat ground but that doesn't seem to be the case.  Mechanic advised to not mess with the jets or that I'd be back in there.  I recall reading somewhere where the main jet doesn't actually kick in until the last 1/4 or so of the throttle and that's where I feel like its limited.  Not sure what to do about that unless that's just a characteristic of a 49cc unrestricted scooter.  I assume I've unrestricted it to the extent it can be.  He said a big bore kit would be next if what he did didn't provide the result I was expecting.

Like I say, it does way better on flat ground and a fair amount better on a hill.  Just wondering about the lack of smooth throttle response as I slowly open it up.  Comments/suggestion?  Thanks.

[xsel777]

From what I have read, is that jetting is highly experimental, in that you must have a stash of different sizes and try them out in different combinations, to get your target behaviour. Lots of time and patience needed.
In my opinion, it has a mystical quality, this getting the jets just right thing.
If what the mackie has done is all correct, perhaps a sports variator? / and /or clutch ?

I know that rollers diameter and weight play a major roll in pull away and top end.

You should really search youtube for poor hill speed(a suggested search string).
I am sure something will come up that you will find useful.

Sent from my MI MAX using Tapatalk

[dwbaily]

Thanks for the suggestions.  I've read too about the jets issues.  Not sure if that would be a significant player in the lack of smooth throttle response or what. 

The rollers must be right.  Take off is pretty decent and top end is a fast as it needs to be with the 32 mph limit here in NC. 

Will try a search on poor hill speed and see what comes up.  It was one guy's hill issue where I came up with the 1500rpm spring and 6.5g rollers.  But the mechanic said the 1000rpm spring was best in his opinion and that's what I wound up with.  Thanks again for the comments. 

[dwbaily]

So still having the chugging problem going up hill with on 165 pounds on it.  Change in variator, spring and rollers helped but surely it shouldn't slow to like 15-20 mph should it?  Pulls a little better after the change but not much.  Takes off at the top of hill. Any other ideas? 

[dwbaily]

Pilot jet was clogged and tweaked air/fuel mixture. Runs better but still slow on hills. Maybe drop rollers from 6.5 to 6.0?

[Redk]

This is Not really difficult to explain.

Power/Weight ratio = Speed.

The best way to dominate that hill would be a larger displacement engine with more horsepower and torque.
It is a simple solution.

A big bore kit might get you up that hill 5-10mph faster, at a significant loss in reliability to all drive components downstream from the crank.

My best advice would be that you stay within the regulations of your jurisdiction to avoid harsh consequences that will affect you far on down the road.

Enjoy riding the 50, for what it is.  It's most likely you shall upgrade in time.

I can picture you doing a wheelie up that hill ! (And those exhibition/reckless citations are Really pricey ! Don't get caught ! )
redk