A few faults i found while rebuilding

[con]

first thing i did was to strip down to last nut and bolt, then started to rebuild properly.
engine wise fitted the recommended clutch springs, bearing and small end bearing also replaced mains and transfere shaft bearings with genuine plus gen transfere shaft (they are so much stronger) genuine polini seal kit fitted with gen water pump pulley and belt kit ( the rep waterpump pulley cut drive is very slack and i can see it failing , well worth changing instead of seizing ur motor up) gen coil and pick fitted as my pick ups were dead short from the box! header tank fitted .
the aux exhaust ports were partially blocked and transferes partially blocked with overplating so these were cleaned up , (if anyone wants theirs doing i can do these as i tune twostroke racing engines as my 2nd job) the carb rubber internal diameter needs opening up to match the carb diameter (what a slack manufacturing error!)
the exhaust stinger was almost 50% blocked with a blob of weld! plus no packing in the end can so repacked ,
fitted one of scott finlays jet kits and machined choke plunger to allow proper seating , conti filter ,
oh the fuel tap was assembled back to front so it didn't flow fuel!! strip down and turn around the small disc with 2 holes in it , it's easy to work out!
chassis wise a coat of quality black paint afer removing weld spatter looks soo much nicer
front wheel bearing spacer was a mile too short and had caused bearings to run rough , replaced with quality british bearings and longer spacer made for the wheel center.
the head seems to be porous (oil and water droplets appearing from nowhere!!) but will see after sat when it has it's shakedown.
hope this helps anyone overhauling their gp3.

i've had a buzz aroung the garden seems nice and crisp , but how tiny are they compared to a 911!!!! i'm wedged between the tank and seat unit!! ;D

[Matt]

Someones been busy!
How much did you spend?
The bike sounds great with a Black frame. ;D Upload a picture into the 'members bike pictures' area-i havnt seen a GP3 rep with a black frame yet!

Enjoy your riding!

[con]

Matt , i got the bike fairly cheap off ebay £249 inc postage , i'd say ive spent another £200 plus tyres (pmt t41's) but I'm hoping it's sorted now for a while will take some pics of the bike at this stage the bodywork is next on the adgenda , hoping to get some fibreglass fairings made up for the gp3 , i'm not paying polini prices!!
cheers Con

[con]

bike is too small for an old stiff jointed bloke! but i was very pleased with the handling and POWER which it has plenty of!! , i just can't move about on it.
sticking with my 911 because at least i can get my feet on the pegs !!!
so it's FORSALE (really gutted!) alot of work and genuine gp3 parts fitted pm for full details , but it cost me £250 to buy and about £250+ in upgrades will sell for £375

[tony811976]

i reversed the foot pegs left for right which helped me a bit but i do agree the riding position is not too good

[Matt]

yeah i reversed the foot pegs too....im not finding the riding position too bad personally (but im a young bendy person!) it was better on my MK2!

[tony811976]

i have found the fuel tap too close to the exhaust. i cant turn it on or off without it hitting the exhaust and burning myself.
can i ditch the tap and fit an inline tap or is something fitted wrong? mind the whole fuel line is too close for me. ive considered using exhaust wrap
i also noticed that on the choke mod there is a mention the o ring. i dont have one, all i can see is a groove? does it perform an important task as a seal?

[Matt]

ive noticed that with the fuel tap aswell. i just lift the tank to turn the petrol off on my bike....the majority of the time it is left on. As for the petrol pipe, i cable tied mine lightly to the frame to keep it away from the exhaust. If you take the lever off of your petrol tap (they tend to fall off anyway!) you may be able to fit a tap along the pipe somewhere, maybe above the fuel filter-i couldnt say where to get one from though.
I havnt got an O ring on my choke either. I know that a few people havnt. when i took it apart i concluded that on my choke there is nothing to seal, so i asume that the older models may have been different
Hope that helps! lol

Just read your rant...i totally agree! Thats why i set up the website, to try and help the people (like me!) that were caught out! Im glad it helped you!

[tony811976]

i hope this site stays friendly its nice to be able to ask simple questions and get a friendly answer ive used an other minimotoforum site and all that you get is slated for having a rep and go and get a proper one

[con]

Tony and Matt
the oring on the choke is pretty important as it seals the excess air to the fuel enrichment circuit (choke) , if this still bleeds air past you may find unusual jetting problems?
mine has got an o ring fitted but it is quite tight when pushing to choke back down , but i guess they will get looser with use .
the fuel pipe issue was cured on mine after i fitted an extra inline filter , this allowed me to route the pipe away from the exhaust as i had more length to play with , ps mine didn't have a tap lever! so it's left on all the time.

[tony811976]

thanks . the only issue i have with leaving the fuel on is that if the float leaks a little it could drain into the engine and you will neverstart it . that is a fault on my yz 125 i could never start it without bumping, since turning the fuel off it starts second kick how about using a flexi brake pipe clamp to shut the fuel off when not in use

[Matt]

Thanks Con!
I couldnt find anywhere for the air to leak on my choke, but as there is a groove for an o ring, ill fit one anyway.
Tony, if you want to see any pictures of setting up the choke, just look on the website www.gp3reps.wordpress.com
Also, if you have found that your float bowl is leaking a little, you may need to set up the float, again this is detailed on the site.

A flexi brake pipe clamp should work, as long as there is no restriction in the pipe-which i dont think there will be

[ninjanut]

HI all,
New here with a problem.We have a gp3 rep which my daughter rides,it has been upgraded with polini clutch,coil,small end,air filter,pull start rear sprocket good chain and scott carb kit.
Our problem is, although the bike runs really well and fast at half throttle and above,it seems to bog down when standing at tick over and is very crackly and fluffy coming out of corners back onto the gas.
can anybody shed some light,or had similar prob?Also, when checking float height,is it with floats in up position ie stopping more fuel coming in or down position letting fuel in?
Thanks in advance for any help given.

[con]

ninjanut , i must admit untill i had set the clutch to bite at higher rpm , mine boged and missed , i think it's running a bit rich when not in the power , try dropping the needle a clip (ie move the needle clip up one groove) also have a play with the idle mixture screw before you touch the needle , if it's dieing at tickover it could just be too rich on the idle circuit ;-)

[ninjanut]

Thanks for reply,
yeah, tried both yesterday.mixture screw did,nt seem to change much untill it was screwed all the way in,then started to rev up.dropping needle seemed to affect high rpm.it does look like its rich as we get loads of oil around tail pipe at end of session even though running 50:1.
It does,nt cut out on tickover,is just very unresponsive untill you have opened it up.(not good at start of race).have stripped and cleaned everything,just a little unsure if i,ve set float height right and if this could cause our problem. clutch is set to 8200.