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Ha Ha, great question firerg,

No idea of top speed. Mine's done 92MPH on the speedo (148KPH) 2-up and laden for 2 hours at a stretch repeatedly. Never got above 95MPH indicated (153KPH) one-up - i'm a fat b*st*rd, probably someone little and light may go faster.

Maybe one more tooth on the output sprocket'd give more speed...

 

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Ha Ha, great question firerg,

No idea of top speed. Mine's done 92MPH on the speedo (148KPH) 2-up and laden for 2 hours at a stretch repeatedly. Never got above 95MPH indicated (153KPH) one-up - i'm a fat b*st*rd, probably someone little and light may go faster.

Maybe one more tooth on the output sprocket'd give more speed...

i am a little lighter and i have ur old engine lool ive had her hit the ton mark 1s on a nice smooth road no wind etc loool but 80 85 90 not to hard 2 get on em
 

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It's mean that standard RG 125 goes like 90 mph or 145 km/h ?
Hi firerg,

It's as well to remember that the RG125 Gamma was sold here in the UK as a learner bike so was only supposed to give 12 1/2 BHP output.

However, the RG125 Gamma engine is basically 1/4 of the GP winning RG500. The engine is good and can be well tuned. Ok, so it's a reed valve engine, not a disc valve one but with tuning (ask Dan) can produce more BHP.

Back when the RG125 Gamma was built, the only restrictions to engine power output were down to carburettion, exhaust tuning and ignition. These old bikes don't have the complex electronic engine control system of the later RG125 Fun.

These little bikes can easily exceed the old magic 100BHP/litre limit. The thing is, do you trade reliability for power output ? The little Gamma engine can probably produce 40 BHP for a short time (i.e. an hour on the race track a week between weekly engine re-builds) but is it worth it ?

A mate of mine can get 70BHP out of an MZ 125 for a very short time. Most Aprillia RS125 (Rotax engine) can do this. Look at the 125 and 250 races on telly before the GP races. They're lots more fun


 

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Something must be wrong here, the RG125 gamma is faster than the TZR125 (OLD style 1990), and I was hitting indicated speeds on the clock of over 90 MP/H on my TZR, and believe me the bike felt like it was about to fall apart at that stage. Wasn't even redlining it.

Maybe it's because of my weight? 5'2", 110 lbs.


If the Gamma isn't doing 90+ derestricted then 1 possibility is you're too big. THe bike is very small, it's very light, and designed for small and light riders.
 

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Ha Ha, great question firerg,

No idea of top speed. Mine's done 92MPH on the speedo (148KPH) 2-up and laden for 2 hours at a stretch repeatedly. Never got above 95MPH indicated (153KPH) one-up - i'm a fat b*st*rd, probably someone little and light may go faster.

Maybe one more tooth on the output sprocket'd give more speed...

 

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Ha Ha, great question firerg,

No idea of top speed. Mine's done 92MPH on the speedo (148KPH) 2-up and laden for 2 hours at a stretch repeatedly. Never got above 95MPH indicated (153KPH) one-up - i'm a fat b*st*rd, probably someone little and light may go faster.

Maybe one more tooth on the output sprocket'd give more speed...

You must be joking an rg 125 doing 92 mph with 2 up for 2 hours , who could sit on the back of an rg 125 for 2 hours .
 

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hi,
i can get my old gamma up to an indicated 110mph,(probably a real 99mph, with the speedo over-reading by 10%) with just a micron exhaust as extra,& an a silly sprocket set up & with the engine having a full rebuild. i wouldnt do it for any length of tome though,lol
so at a guess, stock uk bike (with no pv & exhaust gutted or replaced) would see 85-90mph

cheers,
GAZ
 

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You must be joking an rg 125 doing 92 mph with 2 up for 2 hours , who could sit on the back of an rg 125 for 2 hours .
A sweet young lady ex of mine.

We were "Sealed Knotters", that was on the way back from a fight in Yorkshire.

She learned pillioning from sleeping on the back of her brothers Honda Maggot when he was a courier.

She has a small bum and a very good sense of balance.

 

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We were "Sealed Knotters"
As in "Peeled Nutters"? :p

Mines an '88 RG125 UJ. Nothing changed apart from a Micron Exhaust.
Will be nice to see what it can do when I get it running.

I passed my full test over two years ago, bought this then haven't ridden a bike since.
That's right through 1 year of 'R' plates and 2 of 33bhp restriction...
 
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