GP3 rep & GRC rep info?

[grantman]

I have had a hunt around and found some info for GP3
http://gp3reps.wordpress.com/factory-problems/

is this info still good for my GRC rep?
I think so
What do think is worth doing?


Thanks
Grant

[DELLORTO]

so what do you have in mind for "worth doing" grant? do you mean modifications??

[BigAl]

Very interesting Grantman, I would start with the easy mods and will definitely be checking out some of the 'so called problems' on my bike.

As there are different factories making these bikes then all the points may not apply.

That air filter replacement seems a real good idea, let us know if you find anything locally.

later

[grantman]

Hi Max & BigAl
I not really worried about mods to make it faster
(fast enough for me at the moment)

keen to do some easy things first

Cheers

[DELLORTO]

ok grant first i would get some decent tires of arnie {pitwerkz} on trademe and i would install a full filter.....any more to add to that Alan??

[Ray LeCheminant]

Hi Max & BigAl
I not really worried about mods to make it faster
(fast enough for me at the moment)

keen to do some easy things first

Cheers

Hi Grant, the best bit of advice we ever received was to put some SAVA tyres on.....Connor has never looked back.

Contact "grego" or go to www.xminimoto.co.nz for details....they have an online shop....and Greg gets these on the courier very quickly.

SAVA's are the way!!!!

[DELLORTO]

Hi Grant, the best bit of advice we ever received was to put some SAVA tyres on.....Connor has never looked back.

Contact "grego" or go to www.xminimoto.co.nz for details....they have an online shop....and Greg gets these on the courier very quickly.

SAVA's are the way!!!!

it realy depends on your riding style and how you use them.......for example brett has had lots of trouble with his sava's e:g and mt wellington last month his tires got giant bubbles so he couldnt ride and he had a "cut" the length of the tire on his rear tire........and then other people love their sava's and find their perfect for racing.....i personaly prefer PMT's becasue there just softer but thats just me.....

[Gadgit]

I run a Polini GP3 a rep GP3 and a rep GRC with reverse engine. The best you can do to keep them reliable is -1. fit a new small end bearing (not a chinka one) 2. Have the main jet in the carb sized and fit a larger one (2 sizes up they are always too lean out of the box) 3. When you start it don't just randomly pull on the start cord, pull it slowly up to compression then give it a pull to start. the starters are week but I have never blowen one yet. 4. Keep the air filter clean as when it gets dirty you will begin to feel it miss in the mid range and you can chase your tail for hours changing spark plugs and eletricts to try to rectify the fault ( I should know lol) 5. Keep a spare flywheel and stata on hand as this is the only part on my engines that I seem to replace on a regular basis.... Hope thats helpfull to ya.

[Ray LeCheminant]

it realy depends on your riding style and how you use them.......for example brett has had lots of trouble with his sava's e:g and mt wellington last month his tires got giant bubbles so he couldnt ride and he had a "cut" the length of the tire on his rear tire........and then other people love their sava's and find their perfect for racing.....i personaly prefer PMT's becasue there just softer but thats just me.....

As you say Max it comes down to personal preference.....but Mt Wellington (from reports as I was not there) was extremely HOT....I have raced all sorts of cars/karts/speedway over my many years, and the general rule of thumb on a HOT HOT day is to increase tire pressure to stop them getting too hot....we ran Connor on SAVA at Taumaranui on 7th Jan for testing, and that was the day that the Desert road melted, and it was DAMN HOT (37c) and we ran 4psi higher than normal and the tires were fine.

We ran 20psi and did 10 laps and the tires increased considerably in temp and expanded to the pressure to 28psi.

Run 2 we started at 26psi and did the same laps, and only had a slight raise in temp and the tires did not increase in psi at all, and maintained their adhesion

The hotter the track, the more malleable any tire gets and it attracts heat as the side walls are generating heat through movement....that heat transfers into the carcass and raises PSI and affects the compound...hence blistering, and in extreme cases, delaminating....I have seen kart tires do this

Just my 2 cents worth....but I have been doing this for a while now Max....and believe me I have ruined many good tires until I figured it out

[xtreme]

Ray , you took the words out of my mouth !!!!!!!

Max , yes you are correct with what you stated with what happen to the tyres at MT Welly.

But what Ray said is dead right !!!

I have had a report back from the experts which has stated that the tyres concerned were run at to LOWER pressure for the temp on the day and the weight of the rider , causing overheating & delamination of the tyre carcass . Low pressure = more heat and with 30 deg that day the tyres were fried. The tyres concerned should have been at , at least 30 psi to help keep the tyre cool.
I know some one else that was there on the same day and runs 30 psi using the same model tyre on his open bike and has never had a problem like this.

So this is a learning curve for us all about tyres and is not a fault with the tyres at all.

Also
Someone asked me the HP of a standard GP3 rep and i have been advised that its approx 8 hp out of the box . These bikes looking at the rules fit into the Senior B class and above , to much HP for any class below that ( SEN A etc )

If anyone is not sure about what pressures to run in their Sava tyres please email me , greg.o@xtra.co.nz

Hope this clears up a couple of things

Cheers Greg

www.xminimoto.co.nz

[DELLORTO]

then how come my PMT's didnt mealt??? and im leaning over way more than brett and i raced on the track longer?? i mean my PMT's are over a year old ive never had any trouble with them.....

i guess bret was just unlucky...

[Ray LeCheminant]

Ray , you took the words out of my mouth !!!!!!!

Max , yes you are correct with what you stated with what happen to the tyres at MT Welly.

But what Ray said is dead right !!!

I have had a report back from the experts which has stated that the tyres concerned were run at to LOWER pressure for the temp on the day and the weight of the rider , causing overheating & delamination of the tyre carcass . Low pressure = more heat and with 30 deg that day the tyres were fried. The tyres concerned should have been at , at least 30 psi to help keep the tyre cool.
I know some one else that was there on the same day and runs 30 psi using the same model tyre on his open bike and has never had a problem like this.

So this is a learning curve for us all about tyres and is not a fault with the tyres at all.

Also
Someone asked me the HP of a standard GP3 rep and i have been advised that its approx 8 hp out of the box . These bikes looking at the rules fit into the Senior B class and above , to much HP for any class below that ( SEN A etc )

If anyone is not sure about what pressures to run in their Sava tyres please email me , greg.o@xtra.co.nz

Hope this clears up a couple of things

Cheers Greg

www.xminimoto.co.nz

Also
Someone asked me the HP of a standard GP3 rep and i have been advised that its approx 8 hp out of the box . These bikes looking at the rules fit into the Senior B class and above , to much HP for any class below that ( SEN A etc )


Greg,

At 8HP that would mean the GP3 Rep bike cannot be run in Junior open, correct?

Ray

[DELLORTO]

Also
Someone asked me the HP of a standard GP3 rep and i have been advised that its approx 8 hp out of the box . These bikes looking at the rules fit into the Senior B class and above , to much HP for any class below that ( SEN A etc )


Greg,

At 8HP that would mean the GP3 Rep bike cannot be run in Junior open, correct?

Ray

why you taking about a gp3 running in junior open?? also a zpf is suposibly 7-9hp

[grantman]

Thanks guys for all the info

Will look into some tyres soon
Got some bills to pay first

There is always something!
did a bit more work on my bike tonight
slowly getting it back together for next meeting

Thanks again
Grant

[xtreme]

Max

I think you and your bike are a little lighter than then the other guy and you probably had pressures more suited to you and your bike, read the previous 2 posts carefully and think about it and you will see that it explains what can happen if you run the wrong pressures in the wrong conditions !!!!!!!


Cheers Greg