125-200cc Cylinder Honing

What honing attachment for a handheld drill do you recommend to hone a 2012 CR125 cylinder? What material is the cylinder made out of?

Never Heard about a handheld honing device I am a bit skeptical about that.
the cylinder is plated with a nikasil liner as far my knowledge goes.
Robert-Jan

http://www.baileysonline.com/shop.axd/ProductDetails?item_no=240AO 51&utm_source=nextag&utm_medium=cse

They exist - I don't think it's meant for repairing a cylinder wall that has gouges. It's probably meant more cross-hatching a used cylinder, or even for removing small aluminum buildup from a piston. Nothing major.

Ha ha I had a complete different machine in my mind (big floor standing one) where the cylinder is clamped in to and metal head with 3 or 4 tips are turning into the barrel to rounding the cylinder

this looks like rotating tooth brush to me (no offense)

Robert-Jan

haha oh yeah - i'm not expecting this to do any heavy lifting. I just want to clean up a cylinder

What are you trying to accomplish with the honing? If you have aluminum transferred to the cylinder wall, use a Q-tip and some Muriatic acid to carefully dissolve the aluminum and then flush away.

That is what I'm doing, thanks man! Does honing do anything to aluminum deposits on a cylinder?

View: http://m.youtube.com/watch?v=vaFp8aYkHNA&desktop_uri=%2Fwatch%3Fv%3DvaFp8aYkHNA


Before you hone you might want to watch this.

I much rather use the acid to remove metal deposits on the cylinder walls than honing or using emery cloth. It will not touch the nikasil and will not leave you with an uneven surface that you get with a hand applied abrasive. No matter how you use the sand paper you will be removing lining from adjacent areas.

If you have a scored lining and do not want to spend the money for a re-line then you can use a blade hone with 4" blades and 400 grit to remove the sharp edges. This is a very fast operation using wd40 as the honing oil and making quick strokes with your drill for only 5-10 seconds. Then thoroughly wash with hot soapy water, then clean with wd40, then hot soapy water again and lastly with another wd40 cleaning. But remember you still have a compromised cylinder wall that will wear your piston/ring faster than a new lining. The nikasil lining is so hard that this short honing will remove very little of the lining and only attack any sharp edges protruding into the cylinder plane.

I have been using a returned severely seized cylinder from a 165 on my 09 165 for two years now. I wanted to see how the motor reacted and how it affected longevity. Sealing is somewhat compromised with ~1-2% loss in compression and the ring itself has worn a bit faster/new ring every 50 hours. I did the process from above on that cylinder. This particular cylinder would be considered unusable by me and any other mechanic but I wanted to see how the 165 reacted to running a compromised cylinder. So far so good. I will be tearing it down later this winter and will post pics of the cylinder so you can see the severity of the scoring.

A note about trying to remove nikasil lining with a hone. It takes about 10 minutes of constant honing with the 4" blade hone and 240 grit to remove ~.0001" of lining. I learned this trying to work with a bad lining on my WR360 and ended up just sending it off for re-lining(smart thing to do in the first place).

I'm not 100% sure the nikasil is damaged - I'll use the muratic acid and go from there. Thanks Wally.

Finger hones can do a bit of damage to the nikasil if you aren't using a pedestal drill or incorrect grit. I always use the flex-hone ball brush and it's really only used to take glazing off the walls and like others have said, it's not meant to take gouges from the wall it self and yes, these flex-hone ball brushes are good with a cordless drill....all about trying to restore a surface so that the rings can optimally scavenge.

Like Walt pointed out, you can compromise the cylinder lining get way with it for a short period of time but you can't run away from a relining/replate.

Remember if you are going to use a blade hone 4" blades is the minimum length or you will snag one. The blade hone is much less aggressive than the ball hone. Definitely use as fine a grit as possible. Ball hones are very aggressive and meant for creating hatching and glaze removal on steel cylinders.

What brand of muriatic acid do you recommend? Some brands seem like knock offs or diluted muriatic, will they suffice?

Get the strongest you can find. Diluted will work but it will take longer.

Dip the q-tip in acid and dab it on the spot where the aluminum is. Let it sit for a little and wipe it off. Repeat until the it doesn't smoke or bubble when applied.

If you do a bunch of applications and it doesn't stop reacting you've got a gouge through the nickasil.

Oh yeah, I forgot...

BE CAREFUL! Wear eye protection and rubber gloves and avoid inhaling the fumes. Muratic acid strong stuff and can cause injury or even death if care is not taken.

Muriatic acid is HCL, one of the strongest acids. Be very careful and make sure you re-seal the bottle after use and dilute then dispose of any used acid. If you leave the acid exposed in a confined area you will get tarnishing/oxidation of any exposed metal in the area. As uranys says be very careful as this will cause extreme burns to skin and lungs if inhaled directly.

I agree Kelly as it will compromise the cylinder as stated. Even in the cases above where I am working with a honed cylinder, in the long run it will be cheaper to just re-line. Piston's, rings, and your time will add up over the long haul of using the honed cylinder.

The final act in producing a new cylinder, or when one gets re-plated, IS a honing process. So obviously there are needs and benefits of honing a plated cylinder. It is a polarizing topic, so just do what works for you. Better for a two-stoke than a ball-hone is a "brush hone". They lessen the chance of plating damage at the port openings by the large globs of aluminum oxide found on ball hones.

Muriatic acid is absolutely the best way to remove aluminum galling on any cylinder. But, a WORD OF CAUTION: If the galling is near a port, absolutely don't let acid leach into the port, it will attack the bare aluminum there. Be accurate with the application. Wipe it and re-apply often and check progress. If the plating is fractured under the aluminum gall, you can put an unwanted "cavity" in your cylinder wall. If you must work near a port, grease the port walls to protect them.

I think that it is a matter of being able to completely clean the cylinder wall after honing and the grit level of the hone. The larger the grit(smaller number) the larger the hatching lines become, the faster the wear on the piston/ring. The diamond hone process has an equivalent grit of ~1000 and can be precisely controlled to yield a perfectly round and straight bore with very smooth walls = long lived pistons and rings.