KB Jet exchange

[Racey Rider]

When going to a different track us two stroke owners need to think about jetting for the altitude of that track.

I'm thinking it would be handy to have access to a range of jets to test with.
Jets for my bike are close to $15 each, and when I only need to try a size to see if it's right for a certain track, it's a bit of a waste of it turns out I need another size.

So I'm willing to lend out my jets to others when I'm not useing them. Maybe we can organize a 'Jet borrowing list' It's only like 50c to post them around. But could be very helpful.

I have a KR150 with a Keihin PWK 28mm carb.
Jets are N424-36 in size 138 & 132
Would really like to try jets 135 & 130 if anyone has them.

The idea may not work,, but,,
just trying to save a dollar! :msn-wink:

Cheers.
RAcey.

[Ivan]

the best way is leave the jets stock, I left the RG standered and it did good at Taupo and Manfield with a small bike like that you dont even need to change em it aint like the motor is high performance but good idea any ways could work out

[White trash]

I've got a clapped out Harrier. I'm looking for a hoon in an F-18 Hornet.

Anyone keen for a swap this weekend?

[Racey Rider]

I would disagree Ivan. To my why of thinking, the smaller the motor, the bigger the need to get the jetting just right for any given alitiude.

You may have a jetting setting that works ok at any track, but that must be a compromise setting that is not giving you the best power at one particalar track. Raceing at Taupo is a lot higher altitude than Manfield. Dave (old KB member) used to go down two jet sizes on his RS125 for taupo.
I've yet to test the theroy but it sounds right to me.

And how could they not include the F14 TOMCAT in the top 10 last night?:oi-grr:

[Sketchy_Racer]

Ivan your right but also wrong. all engines need jetting to compensate for different air humidity and heat etc etc, a standard 150cc 2 stroke would need to be jetted, only if the air was extramly different than normal (being higher, lower etc) but a 125gp would need jet changes for every tiny little air difference, due to the fact that they are allways trying to run as lean as possible, but not so lean it blows up, like yours did ivan.

and racey,

i have read that you have removed you air filter?? am i correct?

now if so did you change the jetting when you did this to suit more air flow?? if not this would explain whay you bike has seized on (how many times, i dont know ????) so yes you definantly need to change your jet, providing you havnt already.

sooooo

ill go look in my jet box and see what i can do for you ;) :niceone:

Glenn

[Sketchy_Racer]

oh and you should only ever go up one jet change at a time :)

[Ivan]

I would disagree Ivan. To my why of thinking, the smaller the motor, the bigger the need to get the jetting just right for any given alitiude.

You may have a jetting setting that works ok at any track, but that must be a compromise setting that is not giving you the best power at one particalar track. Raceing at Taupo is a lot higher altitude than Manfield. Dave (old KB member) used to go down two jet sizes on his RS125 for taupo.
I've yet to test the theroy but it sounds right to me.

And how could they not include the F14 TOMCAT in the top 10 last night?:oi-grr:

Nah that is actually an idea at Taupo with the RS I will be going down more than 2 jet sizes because it is so cold there

[Sketchy_Racer]

sorry no can do, the largest i have is a 120,
good luck though :2thumbsup:

[Ivan]

oh and you should only ever go up one jet change at a time :)

ah get stuffed use a humidity gauge and then it tells you what size jet to use with the humidity if you get a jet chart lol

[Sketchy_Racer]

ok, thats if you a rich prick with all the fangdangled thingymybops, for us hillbillys, its one jet chande at a time, then a plug shoot :)

[Eurodave]

The RNZAF just exchanged their old Skyhawks for a nice wad of cash, I bet well never see it though, prolly go to all the bloody dole bludgers
On a more serious note, Ive got a good range of Dellorto jets for sale if anyone needs some

[Ivan]

a humidity gauge is 40 bucks and I aint rich I sacrtifice to race I am struggling I need a job next year to pay for my racing

[sAsLEX]

And how could they not include the F14 TOMCAT in the top 10 last night?:oi-grr:
or the HUrricane!

[Racey Rider]

and racey, i have read that you have removed you air filter?? am i correct?
now if so did you change the jetting when you did this to suit more air flow?? if not this would explain whay you bike has seized on (how many times, i dont know ????) so yes you definantly need to change your jet, providing you havnt already. sooooo
ill go look in my jet box and see what i can do for you ;) :niceone:
Glenn

Thanks. I removed the air filter one time at Manfeild as the bike was running very rich, and the plan was to allow more airflow through to correct the mixture. But in removeing the air filter, it allowed too much extra air through, which caused detionation in that instance. Learn as you go.

[Sketchy_Racer]

ok, i see.... ill look at my friend house and see if we have any to suit your needs. :niceone:

[GSVR]

I've got a clapped out Harrier. I'm looking for a hoon in an F-18 Hornet.

Anyone keen for a swap this weekend?

http://www.marineturbine.com/motorsports.asp

[phaedrus]

a DIY jetbike http://www.badbros.net/

[Bert]

Nah that is actually an idea at Taupo with the RS I will be going down more than 2 jet sizes because it is so cold there

though temp is a factor - the main problem is the amount of oxygen & nitrogen avaible it the air. the change in high effects more than temperature.
as does the barametric pressure and humidity.
note. most regional councils / metservice monitor barametric pressure and humidity & temperature
- also if there is a Airport near by you can generally ring them or find their web site (small air feilds are the best) , its worth noting down the pressure for the day to sort out your own jet chart.

I'll dig out the web sites and post them soon

[Bert]

Following up on my last tread -
manfeild - http://www.horizons.govt.nz/maps/map.asp I'll make sure that real time barametric pressure will be on the site after christmas. or visit
http://www.metservice.co.nz/default/index.php?alias=palmerston_north
note its nearly always 0.5 degrees warmer in feilding if the wind isn't blowing.

Auckland - http://www.metservice.co.nz/default/index.php?alias=auckland

and so on.
the humidity, temp and barametric pressure is on the mid left hand side and is updated every 3 hours. not that much use if you want really defind information but its better than nothing.

[Bert]

Following up on my last thread -
manfeild - http://www.horizons.govt.nz/maps/map.asp I'll make sure that real time barametric pressure will be on the site after christmas. or visit
http://www.metservice.co.nz/default/index.php?alias=palmerston_north
note its nearly always 0.5 degrees warmer in feilding if the wind isn't blowing.

Auckland - http://www.metservice.co.nz/default/index.php?alias=auckland

and so on.
the humidity, temp and barametric pressure is on the mid left hand side and is updated every 3 hours. not that much use if you want really defind information but its better than nothing.

[RG150&SV650#96]

Racey Rider:You dont need to to piss round with jets (only if its a serious problem) I raced my RG 150 for two years and never touched the jet and never had problem.

Use 96 pump fuel,leave all airbox covers on and dont cut holes.

[Sketchy_Racer]

yea but yours is a suzuki..... his is a Krapasaki..... it neeeeeeds maintanice :yes:

(pt)

[Ivan]

your not even aloud to do a thing to airbox on street stock either

[RG150&SV650#96]

Your only reviving a shitty old horse racing the KR spend yah time and money on an RG and you will find your riding skills will rise.

[Sketchy_Racer]

Ditto on above.

ive learnt this, The hard way

[Racey Rider]

Interesting thoughts. Care to back it up with some facts and figures??

I have heard just as many people say that KR,s are fast as those saying KR's are slow. Kr's seem to have done well in the past. Last years top 2 Vic Champ riders were on KR,s. Not saying your wrong, but lets hear the reasons.

Racey.

PS. Also looking for some bigger jets to try now.
Keihin PWK 28mm carb.
Jets wanted are N424-36 in size 142 & 145

[Sketchy_Racer]

screw the facts and figures...

are you getting your arse kicked down the straights?? if so get the same thing as whatever is beating you. :done:

[Racey Rider]

No I seem to be up to speed with the other 150's down the straights.
The 250's seem faster, but I'll just have to learn to deal with them in the corners. There was only one RG that was significantly faster in one race last year, after being slowish all season, so I have questions as to what was done to it.
Yes we need fact and figures, or else its just 'hear say' (read: :bs: ).
This RG was faster than That KR on this day at that track is not good reason to change bikes. That KR may have been set up wrong.
If you can say, I lapped this track in a BT of 1:26 on my RG, but when I tried a well setup KR on the same day, I could only do 1:30, then that is of interest.
and why do you think that was? Was the KR heavy? less power? less lean avaiable?

[Sketchy_Racer]

did you do a 1:26 at the manfeild short circut on a stock RG150??

[Racey Rider]

No. It just a example.

[Sketchy_Racer]

pheew.... yes, well as i have ridden both a KR and RG i prefer the RG..... to me it has more power, a little bit more peaky than the KR, and handles a tad better. The KR i rode was a brand new 2004 one and i expected it better than what it was. But i have always liked kawasaki.... mostly cause i love lime green, but that was my first bike.

[Racey Rider]

Am gearing up for the winter series now.
Anyone got a jet: N424-36 (http://www.motorcyclecarbs.com/N424-36_C89.cfm)in size 142 I could try next Thursday?
Keihin PWK 28mm carb.