125 gaskets

[noobi]

i want to do a piston and ring on my bike (07 EC125)
but my gasgas dealer doesnt have the stock 0.5mm base gasket, i emailed steve at motowest(tuning shop in the states) and he said dont change these unless you do head measurements squish etc, i dont really want to do this
could i just run the 0.3 mm and the 0.15 mm base gaskets to get as close to 0.5mm as possible or is this dumb?

also the piston that i can get is the wiseco GP piston for nikasil bores, steve at motowest said that the plating is nikasil but i looked in the exhauset port and there looks like theres a brown mark on the inlet side of the cylinder, dad says that nikasil wouldnt have that?
also the gasgas GP piston for an 07 ec125 is the same as a cr125 gp piston

this has been on the gasgasridersforum for 3 days and no replys, so i thought id ask you guys

thanks :confused:

[barty5]

i want to do a piston and ring on my bike (07 EC125)
but my gasgas dealer doesnt have the stock 0.5mm base gasket, i emailed steve at motowest(tuning shop in the states) and he said dont change these unless you do head measurements squish etc, i dont really want to do this
could i just run the 0.3 mm and the 0.15 mm base gaskets to get as close to 0.5mm as possible or is this dumb?

also the piston that i can get is the wiseco GP piston for nikasil bores, steve at motowest said that the plating is nikasil but i looked in the exhauset port and there looks like theres a brown mark on the inlet side of the cylinder, dad says that nikasil wouldnt have that?
also the gasgas GP piston for an 07 ec125 is the same as a cr125 gp piston

this has been on the gasgasridersforum for 3 days and no replys, so i thought id ask you guys

thanks :confused:


ask rupe for the contact for the guy in christchuch for gasgas he dealt with he is good with parts there is also a dealer/wrecker is hastings deal with yamaha as well.
And yes the piston is the same as the cr125gp quite a few parts on gasgas swap over to other bikes. As for the brown marks not sure with out seeing looling you need to look at the bore not the exhuast unless its been rebored or sleeved it should be nikasil.

[Rupe]

i want to do a piston and ring on my bike (07 EC125)
but my gasgas dealer doesnt have the stock 0.5mm base gasket, i emailed steve at motowest(tuning shop in the states) and he said dont change these unless you do head measurements squish etc, i dont really want to do this
could i just run the 0.3 mm and the 0.15 mm base gaskets to get as close to 0.5mm as possible or is this dumb?

also the piston that i can get is the wiseco GP piston for nikasil bores, steve at motowest said that the plating is nikasil but i looked in the exhauset port and there looks like theres a brown mark on the inlet side of the cylinder, dad says that nikasil wouldnt have that?
also the gasgas GP piston for an 07 ec125 is the same as a cr125 gp piston

this has been on the gasgasridersforum for 3 days and no replys, so i thought id ask you guys

thanks :confused:


On my 200cc I used the 0.3mm instead of the 0.5mm which was ment to give more compression (didn't notice this tho). I also used a wiseco piston kit in mine and it went fine, and I think you can use a yamaha yz125 piston in yours but you might want to find out more on that first.

If you ring Dirt Action Services 033890080 and speak to a guy called Linton, he know just about everything you could dream of on gasgas bikes. His prices inc shipping are normally better than everyone else to. trust me ring him, he'll know.

[noobi]

On my 200cc I used the 0.3mm instead of the 0.5mm which was ment to give more compression (didn't notice this tho). I also used a wiseco piston kit in mine and it went fine, and I think you can use a yamaha yz125 piston in yours but you might want to find out more on that first.

If you ring Dirt Action Services 033890080 and speak to a guy called Linton, he know just about everything you could dream of on gasgas bikes. His prices inc shipping are normally better than everyone else to. trust me ring him, he'll know.

the yz piston is the same for the gasgas 125s pre 07

triplexmoto in east tamaki are normally really good with parts, and steve the owner is a really friendly guy and normally gets back to me the same day about parts, gave me a number board for free when i broke the gay white one i had, but he said their supplier hasnt got any of the 0.5mm and only have the 0.3mm and 0.15mm

i emailed dirt action awhile ago and it wasnt linton that replied but someone else who didnt want to help much, il just call them instead sometime during the week

rupe, when you raised the compression did you run a higher octane fuel or change anything at all?

[Rupe]

the yz piston is the same for the gasgas 125s pre 07

triplexmoto in east tamaki are normally really good with parts, and steve the owner is a really friendly guy and normally gets back to me the same day about parts, gave me a number board for free when i broke the gay white one i had, but he said their supplier hasnt got any of the 0.5mm and only have the 0.3mm and 0.15mm

i emailed dirt action awhile ago and it wasnt linton that replied but someone else who didnt want to help much, il just call them instead sometime during the week

rupe, when you raised the compression did you run a higher octane fuel or change anything at all?

Thats a shame about the pre 07 thing.

Heard xxxmoto are ment to be good, but not really that close so was cheaper to pay freight than drive to xxx. Plus I did find Linton quiet a bit cheaper, but who knows.

The guy that would of emailed you would of been phil, you need to speak to Linton as he tends to be a lot more helpful. He is also the guy that told me what gaskets to use and what I need to do head wise, when I ordered a Gasket kit.

So yeah just bell him and problem sorted.

Oh and I didn't change anything, but would of for 0.15 gasket.

[noobi]

Thats a shame about the pre 07 thing.

Heard xxxmoto are ment to be good, but not really that close so was cheaper to pay freight than drive to xxx. Plus I did find Linton quiet a bit cheaper, but who knows.

The guy that would of emailed you would of been phil, you need to speak to Linton as he tends to be a lot more helpful. He is also the guy that told me what gaskets to use and what I need to do head wise, when I ordered a Gasket kit.

So yeah just bell him and problem sorted.

Oh and I didn't change anything, but would of for 0.15 gasket.

im pretty sure it was only models before mine, i suppose barty would have picked up if it was the same piston number for a YZ, i asked him if he could get the piston

xxxmoto is a 40min drive each way for us :eek:

yea it was phil, said they could only do jetting etc in person not via email, but re reading the emails now, he sounds like he was ok

what did you do to the head?

just have to find time to call him now, im at school during the week etc

0.3mm it is then

thanks for the help :niceone:

[Rupe]

im pretty sure it was only models before mine, i suppose barty would have picked up if it was the same piston number for a YZ, i asked him if he could get the piston

xxxmoto is a 40min drive each way for us :eek:

yea it was phil, said they could only do jetting etc in person not via email, but re reading the emails now, he sounds like he was ok

what did you do to the head?

just have to find time to call him now, im at school during the week etc

0.3mm it is then

thanks for the help :niceone:


Hang on, mine was a 02 ec200, yours could be different. Safe bet would be 0.3 + 0.15 if you were intending to ride tomorrow.

I used to ring after 6pm and still get through.

[noobi]

Hang on, mine was a 02 ec200, yours could be different. Safe bet would be 0.3 + 0.15 if you were intending to ride tomorrow.

I used to ring after 6pm and still get through.

i am riding tomorrow, but theres no time set for a piston and ring, the bike has got sfa compression atm like 135psi i think, and iv done alot of riding on the piston that was in it when i got it, nearly a year now
im just getting information and ideas for when i do do the piston and ring

they must work late then, or live above the shop

[barty5]

Here follow the link put in your bike info it will come up no match untill you click the single piston option which then give you two options i very much dout it will be the second as this is for a 2mm oversize so ther is no other option. I have check with prox they dont do one at all and a couple of other makers dont either you may find Athena do as they a german made.
Just remember there is only one left with supplier after that it would be a 2-3 week wait min.

[noobi]

Here follow the link put in your bike info it will come up no match untill you click the single piston option which then give you two options i very much dout it will be the second as this is for a 2mm oversize so ther is no other option. I have check with prox they dont do one at all and a couple of other makers dont either you may find Athena do as they a german made.
Just remember there is only one left with supplier after that it would be a 2-3 week wait min.

theres no link mate
2-3 weeks isnt that bad, still dont know when im gonna do it anyways

[barty5]

theres no link mate
2-3 weeks isnt that bad, still dont know when im gonna do it anyways

oops my bad here yah go.

http://www.wiseco.com/

[noobi]

oops my bad here yah go.

http://www.wiseco.com/

thanks for the link

is the one thats in stock the one thats standard size on the website? 762M05400 ?
and yes i doubt that its the oversize one, although i will only know when i pull the head off

is the difference between the GP and the non-GP pistons, that the GP one is for a nikasil bore?

you cant bore out nikasil ae? on the gasgas forums they talk about diamond hones or some sort of ball hone on them to clean the bore up. wtf?

thanks

[barty5]

thanks for the link

is the one thats in stock the one thats standard size on the website? 762M05400 ?
and yes i doubt that its the oversize one, although i will only know when i pull the head off

is the difference between the GP and the non-GP pistons, that the GP one is for a nikasil bore?

you cant bore out nikasil ae? on the gasgas forums they talk about diamond hones or some sort of ball hone on them to clean the bore up. wtf?

thanks

you can mahine them out for a sleeve but the linning is real hard and normally go through a few cutting tips to get it done hence it costs for for that type of bore to be done. I think the gp part just relates to the cr model nothing else you would find that there are other pistons for the cr other than the one listed for your bike going up in smaller sizes. And yes this one in stock is the one listed on the web site for the gp cr. Come see us tommorow large marque with KB logo orange SS VE commodore.

[noobi]

you can mahine them out for a sleeve but the linning is real hard and normally go through a few cutting tips to get it done hence it costs for for that type of bore to be done. I think the gp part just relates to the cr model nothing else you would find that there are other pistons for the cr other than the one listed for your bike going up in smaller sizes. And yes this one in stock is the one listed on the web site for the gp cr. Come see us tommorow large marque with KB logo orange SS VE commodore.

sweet as, will do
we're gonna be there real late, 9:30 or later, red rodeo and a huge blue car trailer and a red van is our camp, we'll try get as close to your tent as possible, i wanna do a kb lap lol

cya tomorrow
thanks for the help

[camchain]

Hey there noobi, I'm no reco expert so the following simply my view. It's common practice to combine 2 base gaskets to get your squish the right dimension and the small .05mm difference shouldn't be any prob unless your compression already maxed up with wrong gasket from start. Remember higher compression is more load on engine = shorter engine life. Don't assume gasket in there is correct, you really need to measure to be sure - it's easy enough to do. Measure before taking cylinder off, but if it's already off, completely clean off old gasket, put cylinder back on without gasket, nip it up and measure difference piston height/cylinder height with a vernier or feeler guages and a straight edge. When measuring make sure piston exactly at TDC, mine doesn't sit quite at TDC due to generator magnet effect, this can be hard to spot if not careful. Be extra tidy when cleaning off old gasket. I use masking tape on top of rags stuffed into case. You don't want gasket fragments getting into your bearings etc.

If your bore is looking a bit tired, get it accurately measured top to bottom and get the correct (maybe oversize) piston for correct clearance (which will be somewhere around 0.05mm). I'd be pretty certain you'll have a Nicasil bore. Not 100% sure your description Re brown marking in port but with cylinder off and cleaned up you'll see nicasil coating does continue into ports a bit (otherwise it would chip/flake at port edges. Nicasil coating looks darker, almost like a varnish. Resist any urge to 'clean up' any raggedy looking port/cylinder edges, you could very easily bugger the coating there). Also, need to be acutely aware that although the coating is extremely hard, it's only as thin as a coat of varnish so don't get me started on honing Nicasil.

[noobi]

Hey there noobi, I'm no reco expert so the following simply my view. It's common practice to combine 2 base gaskets to get your squish the right dimension and the small .05mm difference shouldn't be any prob unless your compression already maxed up with wrong gasket from start. Remember higher compression is more load on engine = shorter engine life. Don't assume gasket in there is correct, you really need to measure to be sure - it's easy enough to do. Measure before taking cylinder off, but if it's already off, completely clean off old gasket, put cylinder back on without gasket, nip it up and measure difference piston height/cylinder height with a vernier or feeler guages and a straight edge. When measuring make sure piston exactly at TDC, mine doesn't sit quite at TDC due to generator magnet effect, this can be hard to spot if not careful. Be extra tidy when cleaning off old gasket. I use masking tape on top of rags stuffed into case. You don't want gasket fragments getting into your bearings etc.

If your bore is looking a bit tired, get it accurately measured top to bottom and get the correct (maybe oversize) piston for correct clearance (which will be somewhere around 0.05mm). I'd be pretty certain you'll have a Nicasil bore. Not 100% sure your description Re brown marking in port but with cylinder off and cleaned up you'll see nicasil coating does continue into ports a bit (otherwise it would chip/flake at port edges. Nicasil coating looks darker, almost like a varnish. Resist any urge to 'clean up' any raggedy looking port/cylinder edges, you could very easily bugger the coating there). Also, need to be acutely aware that although the coating is extremely hard, it's only as thin as a coat of varnish so don't get me started on honing Nicasil.

the multiple gasket thing i thought wouldn't really matter unless it had metal rings or something in the gasket for the water gallery holes? but i doubt that water would get in anyway as the crankcase pressure would be higher than the water gallery pressure?

i measured the gasket with an electronic vernier while its on the bike, i don't know how much it gets squashed by the cylinder but the measure didn't come anywhere close to 0.3mm or 0.15mm so i assume its the stock 0.5mm one

is putting the head back on a problem with the two o rings system, i was told that there not the right size and you need the freeze them to get them to the right size to go on properly?

the only other piston available is 2mm oversize not 0.2, 2 whole mm, how useless is that :doh:

yea dad is very certain that if you even take a nikasil bore near a hone that it will go right through as the coating is only about 0.05 mm thick
may just clean it up with some scotchbrites?

the coating doesn't look shiny when i look through the exhaust port, been told it should look chromey?

thanks for your help :niceone:

[flyingcr250]

the multiple gasket thing i thought wouldn't really matter unless it had metal rings or something in the gasket for the water gallery holes? but i doubt that water would get in anyway as the crankcase pressure would be higher than the water gallery pressure?

i measured the gasket with an electronic vernier while its on the bike, i don't know how much it gets squashed by the cylinder but the measure didn't come anywhere close to 0.3mm or 0.15mm so i assume its the stock 0.5mm one

is putting the head back on a problem with the two o rings system, i was told that there not the right size and you need the freeze them to get them to the right size to go on properly?

the only other piston available is 2mm oversize not 0.2, 2 whole mm, how useless is that :doh:

yea dad is very certain that if you even take a nikasil bore near a hone that it will go right through as the coating is only about 0.05 mm thick
may just clean it up with some scotchbrites?

the coating doesn't look shiny when i look through the exhaust port, been told it should look chromey?

thanks for your help :niceone:

oh man i hope i dont have this many problems when i do my piston. i got boyds in hamilton to run the part number off my cylinder and it came back "unknown part number" :doh::doh::doh:

[Rupe]

the multiple gasket thing i thought wouldn't really matter unless it had metal rings or something in the gasket for the water gallery holes? but i doubt that water would get in anyway as the crankcase pressure would be higher than the water gallery pressure?

i measured the gasket with an electronic vernier while its on the bike, i don't know how much it gets squashed by the cylinder but the measure didn't come anywhere close to 0.3mm or 0.15mm so i assume its the stock 0.5mm one

is putting the head back on a problem with the two o rings system, i was told that there not the right size and you need the freeze them to get them to the right size to go on properly?

the only other piston available is 2mm oversize not 0.2, 2 whole mm, how useless is that :doh:

yea dad is very certain that if you even take a nikasil bore near a hone that it will go right through as the coating is only about 0.05 mm thick
may just clean it up with some scotchbrites?

the coating doesn't look shiny when i look through the exhaust port, been told it should look chromey?

thanks for your help :niceone:


Didn't have any problem with the rubber ring things on the head, the new ones fitted fine.

When I checked on go fasters website there was about 4 different sizes, for how much use the bike had done. Emailed them for a price shipped to nz, and they just gave me a price for a wiseco and said better to just use that. So ordered a wiesco for mine over here and it was one size fits all, ran great with it.

[noobi]

Didn't have any problem with the rubber ring things on the head, the new ones fitted fine.

When I checked on go fasters website there was about 4 different sizes, for how much use the bike had done. Emailed them for a price shipped to nz, and they just gave me a price for a wiseco and said better to just use that. So ordered a wiesco for mine over here and it was one size fits all, ran great with it.

ok good thing about the rings then

yea i look there for parts, but with the shitty exchange atm, it would be cheaper to get the piston, ring, clip, pin that barty can get
sent them an email now asking about pistons


steve, yea hope its not much of a drama ae, our local honda shop seems to be able to get all the ktm bits we need, they have parts manuals for most of the models in their workshop, we were in there today cuz the rear wheel bearing on dads ktm collapsed yesterday :oops:

[camchain]

The thickness of your base gasket is what determines your compression ratio, that's what I meant by squish (not amount gasket compresses). There'll be a correct dimension for it, this varies depending on bike/model. Eg, My 200 is 0.0 which means top of piston is flush with top of cylinder shoulder. But pre 2003 200 engine correct dimension was 0.5mm (I think).
There are slight variations with any mass produced parts, hence different gasket thicknesses available. KTM has gaskets in .25mm increments, two gaskets combined to get correct dimension is fine, you shouldn't get any leaks from this. Use a torque wrench.

As rupe mentioned, you shouldn't have any probs with the head O rings fitting neatly.

That 2mm oversize piston sounds like it might be for a 150cc kit (?) - for another bike. Find another dealer. Oversize pistons (for nicasil bores) come in tiny 0.001mm increments.

The Nicasil coating thickness varies a bit but from what I can gather it's usually around 0.1mm Nicasil is super tough but wear tolerances are v small, eg KTM = 0.025mm so be extremely wary about any honing. I used a scotchbrite pad and some CRC to break down glaze but be careful as it's still an abrasive. Nicasil isn't shiny like chrome, it's darker than the aluminium underneath. When cylinder off, if you look closely you'll see the difference where coating stops just inside ports.

BTW, make sure you put the wrist pin 'C' clips in with opening facing down or up. If clip opening at horizontal position, piston speed can force the clip open and pop them off = lunched engine.

[cheese]

BTW, make sure you put the wrist pin 'C' clips in with opening facing down or up. If clip opening at horizontal position, piston speed can force the clip open and pop them off = lunched engine.


Wow that's something I didn't know. I think I put mine facing down anyway just cause it fitted easier like that.

[barty5]

BTW, make sure you put the wrist pin 'C' clips in with opening facing down or up. If clip opening at horizontal position, piston speed can force the clip open and pop them off = lunched engine.

Wouldnt the force hace to cause the clip to close up as they are spring loaded they are made too big for the hole they fit through then they sit in a groove. Sounds more like clips that havnt been put in propely to start with or reusing the old ones.

[camchain]

I'd say you'd be dead right about probs with clips being bent, re-used etc Barty, they can be a bit tricky to get in cleanly. Can't remember where I read about clip position thing but I've come across it more than once. Possibly more a theoretical thing but it can't hurt. If clip is horizontal, force tends to want to open clip (like squeezing it in a vice), but vertically it can't go anywhere. I understand it's less of a concern if using stale gas. lol.
(Stale gas good for milder power delivery which is better for those of us with crook backs Cheese.)

[cheese]

LOL hey I ran the stale fuel through and then it went mint as. Front wheel wouldn't stay down!!

Anyway, the CRs are so powerful that they need a bit of taming down to bring them the the level of the other bikes out there.

[camchain]

Ha ha. Glad you got out for a decent ride cheese. Doesn't take long to loose the bike fitness if not riding regularly. Stale body.

[LittleJohn]

Just get a real bike Noobi!!!!!! Something that is unpredictable, kick ass powerbands and hard to control, just like riding should be...

[noobi]

Just get a real bike Noobi!!!!!! Something that is unpredictable, kick ass powerbands and hard to control, just like riding should be...

whatarya tryna say mate?

[LittleJohn]

whatarya tryna say mate?

get a real 2-stroke not your girly gas gas with it's plush suspension and steering...

[noobi]

get a real 2-stroke not your girly gas gas with it's plush suspension and steering...

its ok, you can secretly like gasgas, theres one the same as mine on tm, you can join the "bikes that have nice suspension, steering, brakes and power club and have sidestands" too if you like

[LittleJohn]

its ok, you can secretly like gasgas, theres one the same as mine on tm, you can join the "bikes that have nice suspension, steering, brakes and power club and have sidestands" too if you like

What a shame I'm so broke and cannot afford it.

Wait a minute I could raid my kids money boxes, I'm sure they have a few dollars that will get me one.

[noobi]

What a shame I'm so broke and cannot afford it.

Wait a minute I could raid my kids money boxes, I'm sure they have a few dollars that will get me one.

smile and wave boys, smile and wave