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 :niceone: )

[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 :headbang:

[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 :headbang:

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 :headbang:

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 :mad: . 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. :blip:

sorry.

[bungbung]

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

sorry.

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

sorry :2guns: :)

[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? :blip:


Bullshit dispensing time: :ar15:

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.

[Ivan]

I am guessing I will get 16 HP out of myne as the Manuals all on the net Standered say that the bike pulls 16 mynes just been rebuilt with after market parts on it for high performance

[k14]

Maybe that's a coincidence that it’s written next to RS125 then isn’t it? :blip:
Nah not a coincidence, my rs doesn't make 45hp, be lucky to make 40 probably closer to 36 or 37 at the moment, considering its done about 2000kms on the current crank and over 800kms on current piston and ring (rebuild after this weekend).

The reason I have 45hp next to my bucket is just a joke, I didn't think anyone would be gullable enough to believe it, just as likley as say for instance a VT250 having 40hp. Ivan, you have alot to learn. :woohoo:

[Ivan]

So many people talk shit that you dont know what to believe I mean someone could pull 45 horses out of one if they tried, I get 40 out of myne

[Ivan]

my rs i mean

[speedpro]

On John Connor's home made dyno mine made 22.5hp. That was quite a few years ago and it still has the same everything so I expect it's making a bit less now. Comparisons between John's dyno and a local shop dynojet gave very similar readings, and performance wise my bucket was similar to buckets making supposedly similar horsepower. With current technology I can't see 40hp for a bucket though high 30s at the crank is achieveable, for a 2-stroke. Not for those pussy other pieces of shit with all the moving bits.

[Ivan]

Homemade Dyno, HMMMMMMMMMmmmmm a new project I'm keen on it, What do you think performance wise adding a set of chambers will do I'm going to get them made to suit the bike, so that means It will have tons of small short power I want a narrow power band as well

Watching my little brother race it is going to be cool he is a pretty determined little prick

[F5 Dave]

Further to the bull dismissing. What manufacturers claim is about 20% more than you would read on a dyno. They measure from the crank & are still a bit optomistic.

Their weight figures are total lies as well, but that's another story.

[Ivan]

So what do you think is the bike is pulling in horses then, I just had it power standing up the drive more grunt than my RGV150 only problem is the chassis handles like a piece o shit, and the Aprilia motors are no good unless you tune em but the frame handles well so I think I am on the iwinning side with this combination

[F5 Dave]

So what do you think is the bike is pulling in horses then, . . .
Who knows? A bike with a weak midrange can feel stronger than one with a nice fat one as the power hits harder when it does come.

Whilst a peak figure that you can claim sounds like a nice way to measure whose bike will be faster, it is rarely the case. Without an infinitely variable gearbox -Spread is more important

Look up the examples in Bell’s book, YZ vs RM125. Modified bikes made more peaky but end up with a spread the gearbox can’t fill.

Read read read.

[Ivan]

OH Reading is so boring I cant read for long, Anyway in the end it doesnt come down to the bikes power it comes down to the rider, Thats were I am allright as is so it adds a perfect bit for me, my RG is slow out the corners and gets blitzed but around the corners im back on people I like leaning it over till my knee hits and opening the throttle alot sooner than normal but advice from Jay has said Im not losing on the straights im actually losing it on the exit as I really hug the inside line and dont droft out alot which brings me out the corner slowert than him

[F5 Dave]

OH Reading is so boring I cant read for long. . .

Yeah but if you did read your writing skill may improve dramatically.


. . . Thats were I am allright as is so it adds a perfect bit for me, . . .

I mean what does that mean? :mellow:

Reading is only boring if you are reading something boring. I find a desire to learn about something I am interested in gets me reading. Use this as a motivator to read more or it will stunt your ability to learn later. The job you want when you are 40 is not the one you get when you are 20.

Then Twist of the Wrist by Keith Code etc for riding. You will learn a lot more than idle chatter from some clowns on the internet (us).

[Ivan]

It means with the bike being fast in a straight line and having out of corner accelleration it will be good for me as I am fast around the first half of the corner then lose it on the exit for starters I hate carparks and 2 I am now so used to Manfield that buckets is hard because you are on something tighter than you are used to and it is not as flowing its all up and down the throttle and gears,

[speedpro]

For some reason this all reminded me of Star Wars and the "force", and whether it was going to be with anyone we know.

Dave's right about the powerband thing and perception of how fast the bike is. Once I got my old TS100 going properly it felt quite sedate, but that was due to the huge midrange it had. It lost the big transition from mid to top end.

[Ivan]

Nah I know and I believe what Dave says he is the bucket legend and also Dave I started reading last night and am learning a few helpful tips what I like to do is read the book when I need to EG if I'm working on the exhaust in the shed I sit there and read about the exhaust system just learning some new stuff Yeah I really like this place most times it has a nice atmosphere and you can learn new stuff

[speedpro]

Nah I know and I believe what Dave says he is the bucket legend . . . . . .
Dave?? Legend?? In his own lunchtime maybe! :dodge:

[dangerous]

Dave?? Legend?? In his own lunchtime maybe! :dodge:
Dave.... Dave who???............. sort ya shit out Ivan, I'm ya man see here bucket legend returns (http://www.kiwibiker.co.nz/forums/showthread.php?t=13390) and here new bucket legend (http://www.kiwibiker.co.nz/forums/showthread.php?t=11596)

[Ivan]

Umm Dave Trustrum and If I can remember right he won the Bucket GP which is bloody hard and I think off of memory won the last 2 hour race at Kaitoke but remember that is off the top off my head, I havent seen you ride Dangerous I have seen Dave ride though and to give young Jay Lawrence a good run is a big thing but at the Momment Jay is the Rossi of Wellington buckets taking 5 titles out in 3 years all back to back 3 in 50's and 2 in opens

[gav]

You wanna get a sense of humour, mate. Clearly you have no idea when someone is taking the piss...... :slap: :killingme

[F5 Dave]

Dave?? Legend?? In his own lunchtime maybe! :dodge:

Kebab I think. Maybe a salad, don’t want to start ballooning.

I didn’t win anything this year, Didn't race the welly 2 hr but me & Si won the first one several years back. last year I got the 50 GP, haven’t raced the 100 one for some while, last time I got a third, but I need to sort a decent handling 100 to look at being competitive esp now the race has been in Auckland for a couple of years. There are some good riders up there & they know their track backwards (literally).

One day I’ll finish my RS100 [insert Tui add]

[Ivan]

Heres some pics of the GT125 as is but remember it is going in a way better chassis but can anyone tell me what I can do to this chassis