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ok so I am looking to rebuild an xcr 440 motor in the future and I kind of know how it all goes but the thing that gets me is honing. I really don't understand that. Advise about rebuilding engines would be great! thank you
 

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When you home out the cylinders, all your doing is pretty much sanding out any type of scratches, or grooves that might be in the cylinder walls. Hopefully their not too deep. You really don't want to hone to much, or you might have to step up your size of piston if their that deep. You'll have to measure the inside after to see how close you are to piston sizing.
 

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Be very careful honing your cylinders, especially if they're nicasil. If the cylinder walls are smooth, I'd just wash them with a sponge and make sure they're clean. I've been told its a BIG no no to use ring compressors on 2-stroke motors. Make sure your pistons are facing the right direction. When you take the pistons out, before you even begin, stuff rags or papers towels or something into the crank case ( Your not going to be happy when you have to take the case apart because you dropped a piston c-clip into the case or the needle bearing exploded needles everywhere ). Once everything is apart, and your ready to put it back together ( new pistons, rings, etc... ), clean the case out because most likely there will be coolant in it. I just use paper towels and dry it up best I can. Next is plugging the case again. I like using caged needle bearings for rebuilds ( makes the assembly process a lot less of a headache ). Careful putting your c-clips in, you dont want to scratch your pistons and have to replace them before its even together. Install both pistons first. Dont install one cylinder and piston, and then another piston after. This makes putting c-clips and rings on a lot less of a headache. Make sure rings are installed correctly ( yes, most can be installed upside down, and will blow your motor within a couple seconds and then you need a new cylinder ). Make sure the ring is set properly on the ring seat. Pinch the piston ring as best you can, and tilt the cylinder as you install it ( making sure the ring does not move from the seat ) to get one sleeve over the ring, and then the other. You're not in the clear until the ring is all the way into the cylinder as it can still grab after the ring passes the sleeve, so keep holding onto it until the cylinder walls are about to pinch your fingers to the ring. Repeat for the other side. Put 2 bolts in each cylinder, and slowly move the clutch around to make sure it doesnt grab. I like to oil the cylinders good with clean 2-stroke oil. Once you feel no grabbing, slowly pull it over by the recoil, then faster, and faster ( making sure your cylinders stay oiled ). Then put it all back together with the proper torque specs, bleed your coolant system, wait for snowfall, and go ride.

I'm willing to bet I missed some steps but I hope that helps.
 

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Mrpipps45 said:
When you home out the cylinders, all your doing is pretty much sanding out any type of scratches, or grooves that might be in the cylinder walls. Hopefully their not too deep. You really don't want to hone to much, or you might have to step up your size of piston if their that deep. You'll have to measure the inside after to see how close you are to piston sizing.
It would be very difficult to remove enough material from a nicasil jug to jump up a piston size. If you could fit an aversize piston then you would already have removed all the nicasil from your bore and you would def know it, cause it would be a flakey shiney mess.

sledcrusher said:
Be very careful honing your cylinders, especially if they're nicasil. If the cylinder walls are smooth, I'd just wash them with a sponge and make sure they're clean. I've been told its a BIG no no to use ring compressors on 2-stroke motors. Make sure your pistons are facing the right direction. When you take the pistons out, before you even begin, stuff rags or papers towels or something into the crank case ( Your not going to be happy when you have to take the case apart because you dropped a piston c-clip into the case or the needle bearing exploded needles everywhere ). Once everything is apart, and your ready to put it back together ( new pistons, rings, etc... ), clean the case out because most likely there will be coolant in it. I just use paper towels and dry it up best I can. Next is plugging the case again. I like using caged needle bearings for rebuilds ( makes the assembly process a lot less of a headache ). Careful putting your c-clips in, you dont want to scratch your pistons and have to replace them before its even together. Install both pistons first. Dont install one cylinder and piston, and then another piston after. This makes putting c-clips and rings on a lot less of a headache. Make sure rings are installed correctly ( yes, most can be installed upside down, and will blow your motor within a couple seconds and then you need a new cylinder ). Make sure the ring is set properly on the ring seat. Pinch the piston ring as best you can, and tilt the cylinder as you install it ( making sure the ring does not move from the seat ) to get one sleeve over the ring, and then the other. You're not in the clear until the ring is all the way into the cylinder as it can still grab after the ring passes the sleeve, so keep holding onto it until the cylinder walls are about to pinch your fingers to the ring. Repeat for the other side. Put 2 bolts in each cylinder, and slowly move the clutch around to make sure it doesnt grab. I like to oil the cylinders good with clean 2-stroke oil. Once you feel no grabbing, slowly pull it over by the recoil, then faster, and faster ( making sure your cylinders stay oiled ). Then put it all back together with the proper torque specs, bleed your coolant system, wait for snowfall, and go ride.

I'm willing to bet I missed some steps but I hope that helps.
Its actually pretty important to hone before you install new rings. If you dont hone then you missed a step. Initially honing will remove any glazeing from burned/buring oil and small carbon deposits as well as smoothing out any scratches or minor inperfections. The most inportant function of honing is the cross hatching it leaves. Youre actually scuffing the cylinder walls and making them a little rough so that as the rings wear the walls smooth again (breakin) they will wear into each other and create a better seal.
 

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Luke said:
Mrpipps45 said:
When you home out the cylinders, all your doing is pretty much sanding out any type of scratches, or grooves that might be in the cylinder walls. Hopefully their not too deep. You really don't want to hone to much, or you might have to step up your size of piston if their that deep. You'll have to measure the inside after to see how close you are to piston sizing.
It would be very difficult to remove enough material from a nicasil jug to jump up a piston size. If you could fit an aversize piston then you would already have removed all the nicasil from your bore and you would def know it, cause it would be a flakey shiney mess.

sledcrusher said:
Be very careful honing your cylinders, especially if they're nicasil. If the cylinder walls are smooth, I'd just wash them with a sponge and make sure they're clean. I've been told its a BIG no no to use ring compressors on 2-stroke motors. Make sure your pistons are facing the right direction. When you take the pistons out, before you even begin, stuff rags or papers towels or something into the crank case ( Your not going to be happy when you have to take the case apart because you dropped a piston c-clip into the case or the needle bearing exploded needles everywhere ). Once everything is apart, and your ready to put it back together ( new pistons, rings, etc... ), clean the case out because most likely there will be coolant in it. I just use paper towels and dry it up best I can. Next is plugging the case again. I like using caged needle bearings for rebuilds ( makes the assembly process a lot less of a headache ). Careful putting your c-clips in, you dont want to scratch your pistons and have to replace them before its even together. Install both pistons first. Dont install one cylinder and piston, and then another piston after. This makes putting c-clips and rings on a lot less of a headache. Make sure rings are installed correctly ( yes, most can be installed upside down, and will blow your motor within a couple seconds and then you need a new cylinder ). Make sure the ring is set properly on the ring seat. Pinch the piston ring as best you can, and tilt the cylinder as you install it ( making sure the ring does not move from the seat ) to get one sleeve over the ring, and then the other. You're not in the clear until the ring is all the way into the cylinder as it can still grab after the ring passes the sleeve, so keep holding onto it until the cylinder walls are about to pinch your fingers to the ring. Repeat for the other side. Put 2 bolts in each cylinder, and slowly move the clutch around to make sure it doesnt grab. I like to oil the cylinders good with clean 2-stroke oil. Once you feel no grabbing, slowly pull it over by the recoil, then faster, and faster ( making sure your cylinders stay oiled ). Then put it all back together with the proper torque specs, bleed your coolant system, wait for snowfall, and go ride.

I'm willing to bet I missed some steps but I hope that helps.
Its actually pretty important to hone before you install new rings. If you dont hone then you missed a step. Initially honing will remove any glazeing from burned/buring oil and small carbon deposits as well as smoothing out any scratches or minor inperfections. The most inportant function of honing is the cross hatching it leaves. Youre actually scuffing the cylinder walls and making them a little rough so that as the rings wear the walls smooth again (breakin) they will wear into each other and create a better seal.
The honer I use is barley that. Since all the cylinders I deal with are nicacil, and I cant afford to mess one up, I just have one with very soft rubber that I attach to my drill and spin it through. Then I clean it with a scotch brite pad or the rough side of a tough sponge. Everyone has different ways of doing things, thats mine.
 

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sledcrusher said:
The honer I use is barley that. Since all the cylinders I deal with are nicacil, and I cant afford to mess one up, I just have one with very soft rubber that I attach to my drill and spin it through. Then I clean it with a scotch brite pad or the rough side of a tough sponge. Everyone has different ways of doing things, thats mine.
So Im guessing the very soft rubber is impregnated some sort of abrasive? As long as your leaving some sort of cross hatching your prob doing the same thing, just with a slightly different tool. I use fine stones when I hone a jug out then wash it with brake cleaner and then hot soapy water. Its probably the same end result.

You should get a spare/useless jug and practice with regular automotive hone. I got mine off the shelf at napa, 4 in long stones. Real easy to do. Use a variable speed drill at about half speed, a little wd-40 or similar spray lube. Go for 10 or 15 sec at a rip moving the hone across the whole bore while spinning the drill till u break the glaze and get a good cross hatch.
 
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