Scoot won't climb hills

Ok. So I'm 17 stone and trying to ride a Peugeot Speedfight 50cc scoot up a hill - and it doesn't like it much.

We have a challenge at work amongst us 'Bikers'. Buy a 50cc twist and go for less than £200 and make it ready for a number of tasks.

Easy! NOT

I managed to get a 2000 Speedfight dirt cheep. It hadn't been used for a few years. It's clean and it runs, however if I ride up a hill to the top providing I had some momentum when I hit the start of the hill, albeit at 20 ish Mph. (Expected with what the poor thing has to carry.)

The problem comes when I stop halfway up the hill. The scoot will not pull away but just bogs down, and I end up turning the scoot around and heading back down the hill.

I have cleaned out the carb, replaced the spark plug and the air filter. The engine appears to be fine and revs nicely when it is on its centre stand.

Replaced the variator with a new one (stock item). Replace the torque spring (1000 rpm) - no better. Replaced the clutch springs for some that would engage the clutch a little later but again no improvement.

It's as if when I'm halfway up a hill and try to pull away the revs don't get anywhere near the power needed to pull me away up the hill and the engine is under heavy load (me).

Variator - stock with 8gm weights
Clutch torque spring - 1000rpm
Clutch springs - Malossi red (sports!)

Any thoughts?






Chips

You need lighter rollers or lighter sliders. That will solve the problem.

I have a couple of 125s, and they won't climb either. Rollers are stock. Just for the heck of it I will try lighter ones and see what happens.

Thank Mark.

I have been concentrating on the clutch so far. I have bought a roller set with weights from 5.5G to 7.0G.

I'm guessing the lighter the roller the later (slower) the variator is closed and the gear ratio stays in 'first' whilst spinning fast enough to engage the clutch.

The heavier rollers push the plate closed early and forces the transmission into higher 'gear'. A bit like pulling away in third or even fourth gear which might explain my issue.

Do I go Big Bang and replace the 8G rollers with the lightest (5.5) ones or will they be to light?

Chips

Are you from top gear? Because you describe something (cheap ride, modded to be put through various tasks) that they would come up with...
You can't be the stig, the tame racing driver never speaks...
And the one hates motorcycles/scooters...
So you have to be james may...he's the most likey to go to the the scooter community of the three...
Well james you came to the right place, these folk have oil for blood.

I wish I had their budget...


Chips

Don't go extreme with lighter rollers. You could blow the motor from over rev. Try the 7 grams. Also, a worn belt will exhibit gearing that is too tall.

New belt came with the replacement variator. I will start with the 7G rollers. And see how it goes. It only takes half an hour to swap them out so I might experiment by lowering the weight by half a gram and taking the scoot out for a hill climb each time.


Chips

Totally new to 50cc scooters. It's a twist and go so there is no manual clutch to feather.

The last moped I had when I was 18 and ten stones (140 pound).

The trouble is the other guys in the challenge have all managed to get a scooter but they are all non-runners. Mine is the only one so far that will run. A couple of the guys are also pretty weighty but we all live some way apart, otherwise I would have got one of them to try the hill on my scooter.

These 50cc scooters are sold to thousands of people but I have never seen a weight warning on any sales documents!

Only to ridden by lightweights....

Chips

It's 50 cc's. While I don't know how steep the hill is, the thought occurred to me that you might be asking too much of it.

Let me be the first to say that's a damn cool challenge you're in. Sounds like fun.

I am going to be brutally honest. You weight more than the scoot. It might poduce 3BHP on a good day. If you want it to climb the hill you should look for a big bore kit.

Outside of the rules of the challenge.

Yeah I know the weight ratio - thanks! But you know that's part of the challenge for me.
If I am riding the scoot at some pace (25-30MPH) when I start the hill climb I can get to the top. It's just if I stop halfway up the hill and then try to continue it fails. Which sort of suggests that it may just have the guts if only I can coax it from a stand still to a crawl - and then who knows...

Part of the challenge is to ride the mighty steed to work. Sounds easy but I live 50 miles from work and the journey includes a couple (at least) of hills.

Now on my GS1200 that's an easy ride of about an hour.

If I can get the scoot to make the hills I'm guessing the journey to work will be a healthy two to three hours.

I have until April next year to make this happen - and keeping within the limits of the challenge I intend to.

Just got to beat those hills........


Chips

I wasn't meaning to rag on you about the weight. I'm 220lb myself, and have dealt with the small engine/ big load metric before.

One thing to look at then is if there is a different final drive gearset that was used on a different model scooter. Gearing down the final drive would likely get you up those hills without losing much on the top end.

Another possability would to read the rules liberally. Is there anything that would prevent you from using a moped? Adding a little "people power" to the engine would definately help on the hills.

If you don't want to buy several sets of rollers to experiment with, buy an inexpensive electronic scale. Mine is a hundredth of a gram scale.
I put a metal burr bit in my drillpress and grind a little out of the inside metal sleeve.
If you have time, go maybe 1/2 gram per roller, I'm assuming you have six rollers, which gives you 3 grams less weight.
I've never experimented on a 50cc before, so I don't know how much it takes to make a big change.
On my 250cc, I went down 1 gram per roller to a noticable change.

No offence taken.

Someone else I know suggested a change of final drive. I think that will be my last resort. I have a set of rollers from 5.5 to 7.0 grams so will star to experiment.

Forty years ago when I had my first and only 50cc moped I can remember using the peddles on occasion to assist me up the hills. So it was a problem then I guess, but I just expected it then...

I'm not giving up though and have to thank you all for you support and suggestions.


Chips

I had the SF2, and it went up hills bone stock, but I agree with what others
have said, lighter rollers, 10% lighter then stock should be more then enough
especially since you already have a rather aggressive spring there.

Brutally honest #2: If you weigh 240 lbs what in hell are you doing with a 50cc scooter in the first place? You should be riding a 650cc Burgman. I read your original post and subsequent posts. You seemed vaguely surprised when, on the hill in question, you stopped and couldn't get it proceed on up the hill? Talk about great expectations.

Really, forget the contest. Get a maxi scooter.

Well you're no fun at all.

These bikes are rated for over 300lbs.

To the OP, are you planning on any mods other than transmission work?

You can get the tuned pipes that are not too loud that will give you an all around bump in bhp.

Is this a carbed bike or injected?