GT125

[Ivan]

Hey does anyone race any GT125's or even GP125's as I was wondering what you can do to set the chassis up, I have added a seat to it but thats all I need to do something with the footpegs but was thinking a more rearset idea but dont know were to hang them

any tips help

Oh and if you can give me any tuning tips it would be mutch appreciated

[TonyB]

I race one. They handle.... badly. There's heaps of flex in the rear end due to the ends of the swingarm bolt being basically free to wobble as they see fit. Welding some extra bits of steel in to retain the ends of the swingarm bolts should work wonders..... I hope. Kickaha tells me that replacing the RUBBER(!) swingarm bushes with brass or nylon will help a lot too.

The standard foot pegs are way too low and too far forward. If you brace the swingarm pivot as mentioned that will give a good place to mount rear sets.

The front end is apparently one of the better ones, and they come with a disc brake that should have a fair bit of stopping power if it's working right.

Mine has completely stuffed shocks, which I'm going to fix. At the moment it is quite effective as a trampoline.

Engine wise mine started life as a GP100, but is now a 125. Still has a 22mm carb (rules allow for 24mm, which is standard for the GP125), and the only mod I've done is add a RZ250 pipe. Like this it has reasonable power, better than most, but still a bit slower than the top local buckets- although some of that may be due to a lower corner exit speed- it all adds up.

Hope that helps Ivan.

[Ivan]

Sweet, Yeah that swingarm did look a bit dodgy, especially with it having no split pins to hold it in either, Life in that chassis is not going to last long I'm replacing it with an Aprillia RS50 but want to get the most out of this chassis whilst I can, How much higher would you mount your foot pegs, as I see a few of you guys racing em, So the carbs are in the rules as well

[gav]

You abit slow at school? A GP125 is a single, a GT125 is a twin ..... :spudwave:
Heres some photos of a GP100 with a GP125 motor, its still a single, not a twin....
At Ruapuna in the weekend, think its from Nelson? (turns out its actually my old GP )

[Ivan]

Yeah I know I mean the chassis are the same
I want to know what mods I can do chassis wise to it. They old skool

[gav]

I see a few of you guys racing em, So the carbs are in the rules as well

So why the comment re the carbs????
My old GP when I had, new owner has got it looking sweet

[Ivan]

I meant "I see a few of you guys racing em. Are the carbs stock on the GT's in the rules? I want to know

[gav]

Don't know of anyone racing a GT125 (twin) but there are a few guys racing GP125's (single), they can use a carb size of up to 24mm. Thought we'd covered all this? You can use the equivalent of one 24mm carb on your twin.

[dangerous]

I meant "I see a few of you guys racing em. Are the carbs stock on the GT's in the rules? I want to know

No one races a GT125 in the south Is...... I was wanting to but couldent find one at the time, then just the other day I find a X4

What size are the carbs on the GT??? this is the problem I'm thinking they are larger than 12mm.

[k14]

No one races a GT125 in the south Is...... I was wanting to but couldent find one at the time, then just the other day I find a X4

What size are the carbs on the GT??? this is the problem I'm thinking they are larger than 12mm.

They are allowed to be 17mm on a twin, we have already covered this ivan . I think someone said that stock they come with 18mm carbs so they would have to be replaced if you want to run it in buckets.

[F5 Dave]

Hey Gav. Nice looking muffler in pic 1. Is that to 'squeeze' more power out of it.

sorry.

[bungbung]

Hey Gav. Nice looking muffler in pic 1. Is that to 'squeeze' more power out of it.

sorry.

That looks like something you might have had a hand in. The chamber is from the same school of aesthetics.

sorry

[Ivan]

Sweet nah these bikes are an awsome little Machine I love riding it it has so much power more than my RG50 I cant wait to see it in action at the next round my little brothers probably racing it he loves the stock chassis but he is a bit mad

[Ivan]

Hey K14 how do you get 45 horsepower out of one bucket and isnt 45 horses almost as much as an RS125

[F5 Dave]

Hey K14 how do you get 45 horsepower out of one bucket and isnt 45 horses almost as much as an RS125

Maybe that's a coincidence that it’s written next to RS125 then isn’t it?


Bullshit dispensing time:

Depending on the dyno (so lets talk std dynojet) the average RS will put out late 30s. A pretty damn good one about 45. Overseas big $ trick one about 50.

There is probably only one bucket touching 20 hp in Wellington & it belongs to Speedpro. My old H100 did 17 & kicked the butt of most (dunno about now with the pipe change & airbox/jetting).

With another barrel/pipe (when I almost won the Chch Battle of the Buckets 4 yrs back, before the bottom end died a few laps before end) it measured 24hp on a pretty optimistic lower hutt bike shop dyno. I suspect this would read 20hp on a dynojet. Made it too hard to ride on kart tracks.

Anyone claiming 22 hp in wgtn is deluded or measuring on a dyno that reads high.