SPEEDFIGHT 100 - More top speed required

[garycollier]

I know I know...get a proper bike and all that. I had a thundercat but got knocked off it twice (written off both times) hence I'm on the pooper scooter to and from work.

As part of my route I need to go on dual carriageways hence require more speed that the basic 50mph that I get at the mo.

Anyone got any advice on how best to get this ? Gear up kit ?

Also - Is it possible to modify the internals of the exhaust for more power ?

Cheers
GAry

[mr jamez]

What about getting a little RXS100 2 stroke, cheap, reliable, fun and do about 70mph I bet the cost of it would equal the amount of mods you would have to do to the ped to get it to go 70mph.

A lot of people on this forum seem to rate them

[Ste]

[divuk83]

Not much more speed to be had from a speedfight 100 I'm afraid. They will do arround 65mph on the clock in standard form and you can get them to about 75mph if you spend a silly amount of money on them. Gear up won't help as it will kill the bottom end if you fit it on the standard bike. It needs to be fitted with a malossi 120 kit which is quite pricey. If yours is a newer one then they have quite restrictive pipes, although I have no idea how to mod it for more speed. You could put a race pipe on but its not going to boost performance loads. I had a PM tuning pipe on my speedy 100 that was pretty good, although it was pretty prone to rusting and bloody loud it did boost speed by about 3mph (wow!) and improve the mid range power.

I would get it serviced first as its sounds pretty slow if it only does 50. As for modding it, just depends on how much you want to spend.

Dave

[loply]

I think your best bet is to sell the ped and get a cheap bike.

Old SR125 or something?

[Milo]

I got a GP100 for £400 and it currently does 60mph on the flat, hopefully I'll be able to take it apart, put it back together and it'll do 70.
But saying that if I have longer/faster journey's to do I do have a XJ900...
____________________
Shaft drives rule.

[RS1Banger]

A friend of mine used to have a speedfight 100, it did 61mph standard and 62 after he spent £100 on an exhaust. It was exactly as quick as my Rieju RS1 moped with the mush on who I bought it off.
The main problem is that they're aircooled and not many tuning goodies are about for them.
Check out www.50cc.nl or www.taffspeed.co.uk or www.pmtuning.co.uk they all sell tuning parts for scooters.
A gear up kit will only help if you're getting straight up to your top speed and revving out, if as you describe, it struggles to pull 60 gearing up won't help.

[garycollier]

Seeing as the throttle cable snapped on the way home from work today I doubt I'll be doing much spped on it for a while...

So while I'm fixing the cable I'll give it a service to try and get it back up to speed. I'v also got my hands on a gear up kit so will try that out in it as well. If its crap I can always sell it for more on e-bay anyaway I'm sure

As for another bike.....I'm renovating an RD125 Mk2 on an '86 plate, so not long and I'll be back on a propper bike so to speak !

GAry

[DM]

[FeRnY]

[mattjholmes20...]

get a gear up kit, thats the best thing you can buy for the money will cost you about £65 but worth it

dont get any big bore kits because you will be forever buying other parts to go with it eg; carb up rated pulley's, clutch weights, carb jets, list goes on,
with all the crap above as well it will not be reliable,

a gearing kit is reliable , it changes nothing else to the engine apart from the gears, it does not make it rev anymore or anything like that so it is reliable, i have put these on a few of my mopeds and with this fitted have been faster than the lads who have spent loads of money on big bore kits ect.. also dont bother with a exhaust for the money they r crap
go 4 gears and super unleaded petrol (higher octane)

[divuk83]

What? Your telling him not to buy lots of bits because there expensive, but to use fuel that is about 5p a litre more and will make no difference at all without modding the ignition.

Don't fit a gear up as in standard trim it will probably kill your acceleration as the bike hasn't the power to pull it.

Dave

[mattjholmes20...]

speedfight 100cc only do about 50mph standard, you can get the 50cc ones to go a faster than the 100cc ones with out spending any money on them, thats just taking the restrictors out of them, and as for the message above !!! what bull sh!t. yes it does slow the pickup speed from setting off, but you can hardly tell the difference in them, does the tit above know about the gearing of one!! the gearing in your standard bike has teeth cut at a angle on them, the uprated gearing has straight cut teeth and the 3rd gear is slightly different in size,

if you race a speedfight that is standard,
and lets say you have the gearing kit on your bike, up to about 15mph the standard bike will slightly pull away from you, but after that you will kill him, trust me its the best and most reliable thing you can do for the money

him with the nail above 3mph out of a exhaust that cost over £100 (waste of money and time) if you listen to him, you might as well set fire to your money!!!

[divuk83]

Didn't realise you were some kind of expert. I had a speedfight 100 a few years ago and wasted plenty of money trying to tune it. Standard 100's will pull to just over 60mph. A Speedfight 50 will do about 50mph de-restricted, but with a half assed 70 kit and taller gearing, will pull to about the same speed as the 100.

While were on the subject of fitting gear ups to standard bikes, yes you will gain a bit of top end, but not if you want to go up hills. I have been on cat and fiddle run with people running gear ups on standard bikes and they had to head home before we got up there as they couldn't make it up the hills

[binge]

Ive got a speedfight 1, tuned to 70cc with all the mod cons etc. It is actually a bloody fast scooter when it comes to hills. I can keep up with a Gillera DNA 125!
I used to own a speedy 100cc, and they are pants for a 100cc. The newest 1 out is pretty nippy, but the old 1. well thats not even worth calling a 100cc, its the equivalant of a 50cc with a race pipe.
id get it going and get it on ebay, you will get a nice 125 for the price you fetch for the speedy, they do well on ebay!

[mchaggis]

[stevo as b4]

I got just about 11bhp r/w outa my SF2 100cc. And you dont want to know what it cost to get there, including the blow up i had along the way! I had:
Doppler exhaust, Polini oversized reedblock and inlet manifold. 21mm carb, modified head to increase CR from 6.6:1 to 7.2:1. Cooler plug, K&N filter, Malossi variator and clutch springs, in a radically lightened clutch, (drilled to look like swiss cheese).

All that, and it would indicate 70mph on the flat and 75mph down hill, but thats a real 64mph or 68mph on a very good hill!
Dont bother tuning one! very slow for a scoot and they dont respond well to tuning, as the increases are very small. The Aprilia SR125 is alot better, and probably quicker std than any tuned Speedfight 100!
Id much rather have had an RXS100, GP125, or KH100 instead!

[binge]

11bhp. is that all!

The RS125 has 20 odd standard dont it?

[stevo as b4]

I know its not much for £500+ is it?! The most i reckon that could be had from 120cc Malossi SF100 is about 13.5bhp-14bhp. It would need everything i had on mine, but with a ported 120 kit, and ported crankcases. Its not an engine that responds well to tuning at all! The 50LC speefight, should make about 7-8bhp with a 70cc kit, but i doubt you'd get much more out of one really.
RS125's vary in power depending on the model, but pre 2003 models should have 28bhp r/w, the new Catayst equipt versions are probably about 2bhp down on that, but thats still 30bhp or thereabouts at the crank!

[binge]

I had my speedfight dynod when I first got it, and At the time it had...
MHR rep 70cc cylinder
malossi Variator + 3g rollers
malossi clutch
malossi gear up kit
malossi crank shaft
malossi 21mm carb
malossi big bore reed blocks
Techingas RS70 pipe...

That pulled out at 10.5 bhp before it was tuned up, and 13bhp afterwards...

Since then ive taken off the malossi clutch cos it was biteing way too late and I didnt like having to red line my ped before the clutch even ingaged... and ive also put 8g rollers in...

I blew it up the other day and Im geting a PM tuning Cylinder put on it (70cc) and Im going to get some feather light rollers for it too...

Then ill take a blast to ashford and get it Dynoed agen.

Ben...

[divuk83]

PM don't make there own cylinders, what they flogging you? Hopefully not a poxy Airsal one.

Dave

[binge]

Hehe, yea. Its an "Airsal".
why, are they bad or somthing?
Its got the same kind of bore as my MHR cylinder tho...
"Airsal 70cc Performance cylinder kits... Aluminium NI + CSI cylinder / Liquid cooled...

I could of got a polini 85cc kit for it, but then theres the chance of blowing the bottom end... And I didnt have £250 + another £250 for labour, So I had to settel for the cheap £100 kit...

Ben...

[stevo as b4]

Well there you go! thats a good output 13bhp for a 70cc SF, as they are not a good motor really for tuning, due to the design and poor intake passages into the motor etc etc.
Ive never seen a 100cc (120mallossi) with more than 12.5bhp, without further tuning. Even so, i would expect 14bhp to be about the best possibly, with further porting work etc.
My SF with 11bhp always had a very slow take off, which after trying so many different things, i reckoned it was the malossi variator causing the problem. I never tried going back to the std one though. I found that my bike would only just stay ahead of an NRG mc3 with a ZX race pipe, on acceleration, and the top end was about 5-6mph better if that!

[divuk83]

Airsal ones are fairly crappy. If you have a hundred squid then its not much more for an MHR rep one. Definately worth the extra cash.

Dave

[Fortuna]

Turbo Nitrous Oxide