engine piston check

erion1

@SpookDog i checked for play when i had it apart it was perfect no up down play slight side to side which is normal and as the bike drank my water before i was thinking it could have litle bit of water in the crank so yesterday i put some 2t oil on the tank for more lubrication on the crank and let it run for a bit so it gets lubed up and maybe prevent corrosion if it didn't happen already

erion1

@SpookDog so you're saying i can rotate the stator if the crank is good, do you mean rotate with hand or with what, and can you explain a bit more what you mean by it would click when shimed with a screwdriver

SpookDog

@erion1

You still have the barrel off yeah?
You should be able to rotate the stator easily by hand. It shouldn’t make any rumble noises or feel clicky/notchy when you turn it…

If you gently lever the stator up and down it shouldn’t have any free movement. It might flex a bit if levered too much…

erion1

@SpookDog no i put everything together as i needed space in my garage and had no place to put the parts and im not runing the bike either so its gona be like that for a month as i don't got the money for the new stuf rn but i'll take it apart again to check that then, but that what you told me is to check the crank bearings right? not the rod bearing it could be good if i can check both of them if they are in good condition without spliting the cases
Thanks for the info!

erion1

@SpookDog i did what you said but i didn't take the cylinder off i only took the sparkplug and took the stator side cover off,
it could be easily turned by hand and it has no movement up or down neither side to side no clicking no nothing just a little friction noisse wich i think is coming from the piston as its not in a good condition

SpookDog

@erion1

Bit of piston ‘scoosh’ is to expected in that condition

The crank turned real smoothly as well? No little stops or notchyness?

Bud! What are the first 3 numerics after the * on your engine and frame? If you let us know we can find out what year and model you have. It’s especially important when it comes to electrics…

MadGyver

@erion1 If you have the original brake hoses,they say manufacture date,99% of the time it's the same year the bike came out of the factory. So with the first 3 alphanumeric's that @SpookDog said and the year of the hose you have the model/year of the bike

erion1

@SpookDog yeah it was smooth only when the piston was going up it got harder to rotate from little bit of compresion as i didn't remove the whole cylinder out,
the frame is a 4DK-006706 the engine is the same

erion1

@MadGyver on the front brake hose it is repeated many times it writes DOT NCRN 12/91 1/8 HL im guessing that 12/91 refers to december 1991 maybe ?

SpookDog

@erion1

That would tie in right. You have the 3 wire servo fitted to your bike don’t you?…
So it’s pre- 96 I think…

erion1

@SpookDog yeah its a 3wire

erion1

@SpookDog i got a top end athena gasket kit but since i have to rebore to 57mm bore will it be a problem ?

SpookDog

@erion1

No, I have a 58 I use (about 140cc)

You do have to check it doesn’t touch the power valve when it gets to a certain size…

erion1

@SpookDog yeah i know about power valve, i was just thinking would the top end gasket be smaller than the barrel but it should be fine

SpookDog

@erion1

It will be…

erion1

@SpookDog yo one last thing i made a video today of kicking the bike over just so you can hear the bike make that friction noise to know if the crank is good, idk maybe just my stress is making me hear it or idk here is the vid https://imgur.com/gallery/HRIy3mb

SpookDog

@erion1

Can’t hear anything over the exhaust! You’ll have to do it turning the stator by hand…

erion1

@SpookDog no i mean the noise that it makes the first 3times that i kick it or maybe its just the normal sound the bike makes when turned over, as for when its runing it doesn't make any noise

MadGyver

@erion1 Have you done a compression test,if something is wrong with the piston or piston rings it should show low compression.

SpookDog

@erion1

I can’t tell bud. Really need to check it without the barrel and piston on it…

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engine piston check