Went ahead and pulled the head off to see what kind of damage has been done. Didn't check the other side, I realize now. How bad does it look? Going to need to hone it again? Also, notice the large gap between the ring stroke and the cylinder top? I put the stock 50cc head back on to see if there is more power. Maybe a little. I'm thinking I should go ahead and get some of that copper spray gasket, and do away with the paper and aluminum gaskets to get more compression. I dunno, I'm new to this. Maybe that is a normal stroke for the rings. I'm going to see if Carlos can ship me out some spare rings just in case as well.
Went ahead and pulled the head off to see what kind of damage has been done. Didn't check the other side, I realize now. How bad does it look? Going to need to hone it again? Also, notice the large gap between the ring stroke and the cylinder top? I put the stock 50cc head back on to see if there is more power. Maybe a little. I'm thinking I should go ahead and get some of that copper spray gasket, and do away with the paper and aluminum gaskets to get more compression. I dunno, I'm new to this. Maybe that is a normal stroke for the rings. I'm going to see if Carlos can ship me out some spare rings just in case as well. Some more pics of the piston and bore would have been nice. It's a good idea to check ring end gaps too.
If you're looking for high speed cruising raising the compression is not the way to go. It's good for squirting around town but you will overheat and possibly ruin a piston out on the road. It's best to err on the low side especially if you road ride a lot. If you do go with higher compression it's best to install a temp sensor on the head with a readout you can see while going down the road
My ring end gaps should be .21mm. They are not that, maybe .17-.19mm at the most. I was afraid to mess with the rings sent with my new kit too much. I'm guessing I've found my seizing problem? Can't be JUST that, can it?
BTW, I'll switch back to the 70cc head tomorrow, too late now, and raining. Only need to go about 6 miles total to work and back, and it's stop and go most of the way.
EDIT: Figured this would be easier than finding a 48mm brush hone around here to fix that scuffing. Thanks for the idea Brent.
48mm = 1.88 inches. Good thing I can use a brake hone, cause those cylinder ones are much more expensive. Will my finished product be affected by using the brake cylinder hone instead of the engine cylinder hone?
Last Edit: Apr 8, 2010 19:51:50 GMT -5 by drawkward
Post by stepthrutuner on Apr 8, 2010 20:42:11 GMT -5
Ring gap should be 0.1 - 0.12mm/in. of bore. That's 0.187 - 0.225mm (according to A.G. Bell). As far as using the larger stone hone go easy. It would be easy to go too far. Use plenty of a light oil or ATF. A ball hone is preferred but they are a little more difficult to come by. If you can't really feel the scratches with your fingernails honing may not even be necessary.
I use PB Blaster or WD40 to hone. Spray the cylinder and hone generously and have at it. Honing is a very quick process so check every couple of seconds. You only wanna do enough to get rid of the worst of it, not necessarily create a beautiful new surface. You have to move the hone up and down the cylinder bore fairly quickly to get a nice crosshatch. I have heard that sometimes the brake cylinder hones with small stones can snag in ports and do damage. No first hand experience with that yet.
I wouldnt hone that one yet bud. I can still see the crosshatch from the factory job, If you have a few grooves, thats ok for now. You really dont wanna hone until its really necessary. If you just have a groove or two, just "smooth' em out with some high grit sandpaper or emery cloth. I ran Skeedr for thousands of miles with the cylinder looking allot worse than you would think. I will post some pics later off my Polini Sport cylinder and piston. It still runs strong but could finally use a piston and honing. It will give you a better idea of 'when its time'. I think your fine for now 8-)! What does worry me is that in your pics it dosnt look like your piston is going all the way to the top of the cylinder at TDC? Looks like the wear marks stop many mm before TDC? Is that true, or is it me?
Those marks are definitely way below the top of the cylinder. I'm about to go check out how far below the cylinder top the piston is with my caliper. My camera is on the frits after I let my aunt borrow it, so I don't know if I'll be able to get a picture. Here is the only picture of the side of the piston I have. I know, it's not very good.
EDIT: just checked it out. here are some pictures. the crest of the piston is actually like .5mm above the deck of the cylinder. Also put some pictures of the plug and oil deposits on the head for feedback.
Sorry they are blurry, my camera doesn't like taking pictures closer than 2 feet. It also has no manual focus.
Last Edit: Apr 9, 2010 16:13:36 GMT -5 by drawkward
I'm no expert, but that piston looks like it's landing just about where it should be. As for your camera issue: look for a button with a picture of a flower. it's made for close-up pictures and it'll give you really good detail.
User manual for the HP Photosmart E317: Use Macro mode to take close-up pictures of subjects less than 1 m (39 in) away. In this mode, the camera will focus at a distance range of 60 cm to 1m (24 to 39 in), and the Macro icon appears on the image display.
Pretty limited on close up shots. It does up to 5mp which isn't terrible. Just under the lens is the "Macro mode switch".
-Photo courtesy of Gizmodo.com
Last Edit: Apr 10, 2010 7:24:29 GMT -5 by drawkward
Removed the mirrors. They just made it look like a bug to me. Removed the floor grips. I like it better that way Removed all turn signals. Going to go with flush mounts soon. -Didn't like the look of them. Removed rear mud flap. Removed rear fender. Dropped the front some more. Removed center stand. Removed rear "rack". Removed ALL stickers. Wish the "eurostrada" was a sticker too. Bought some bondo for that and the holes on the rear panels. Reinstalled kick starter gear
For the immediate future -
Custom cooling fan scoop (in process right after this post) Painting the clutch bell with brake caliper paint to be red. Bondo filler on the rear panels to be smooth and free of holes. Custom under body panel - bondo'd to look like one piece. Relocated "ram-air" intake.
Then when I get the cash -
New bars Manual choke Bigger rear tire for more top speed
Last Edit: Apr 12, 2010 17:34:29 GMT -5 by drawkward