Mac
Member
How is everyone measuring piston cylinder clearance? I have a micrometer that can measure in .0001 increments and thats fine. But only a verner caliper for ID but don't feel this will offer accurate measurement. Does anyone use feeler gages as "go" , "no go" type gages. Also where do you get feeler gages in .0001 increments. Just received cylinders back after plating and I asked for .004 clearance. I want to verify and make sure its .004 and not more.
bore mic is the right way, do ya have a bike repair shop or somethin close and they could measure them for ya real quick? the feeler guage method is kinda caveman like, and not real accurate as you have to really guess as to what you can fit in there by how hard you push it in between the piston and cylinder.
yamaholic22
Active member
Don is the bore mic you are referring to an actual internal micrometer, or are you talking about the tools with the telescoping arms that go out to the diameter of the bore, you lock them in, and then measure that distance with a conventional micrometer.
You might try a snap gage and then use your Mic. to read it .
And use a dial indicator to check the cylinder taper .
Just my .02 .
And use a dial indicator to check the cylinder taper .
Just my .02 .
ya a snap guage I have heard it called before. thats a little bit differnt then what I got though.
I actually have a bore tool though, its a rod with differnt extensions on it with a roller, on the topend of its a dial indicator, you roll it up and down the cylinder and check the run out of the cylinder, you can also check just the width by setting the distance to each side and mic'ing the setting if you just need a bore measurement.
maybe I am not calling it by its correct name?
I actually have a bore tool though, its a rod with differnt extensions on it with a roller, on the topend of its a dial indicator, you roll it up and down the cylinder and check the run out of the cylinder, you can also check just the width by setting the distance to each side and mic'ing the setting if you just need a bore measurement.
maybe I am not calling it by its correct name?
we use thread and two guys. one guy runs a piece of string between his fingers, and gets it to touch both sides, then the other one measures between the fingers. Honestly it works. LOL Naw just kidding. Maxdlx
Concept Carbon
New member
maxdlx said:
vipertripplexxx
New member
Now thats some funny $hit LMFAO!!
Seriously a feeler gauge will work just fine to let you know you have enough clearance.
Sounds like you have wiseco pistons, thats alot of clearance. Check the clearance about an inch from the bottom of the skirt (put the piston in upside-down and leave one inch of skirt sticking out then check it).
Mac
Member
Issues with clearance!
You guys won't beleive the bullshit info out their. Last year Millenium advised me to setup clearance at .0055. When I questioned this amount he said they set motors at this clearance all the time. Drag type motors they setup to .006 or more. Since they are experts at plating I figured they must know their stuff and see it all. Anyway ran about 2000 miles this way last year until I lost compression in one cylinder. When I pulled it apart a cylinder skirt had cracked, not off just cracked. Pat Hauck fixed the cylinder and recommended his Wiseco coated pistons. These are the made for Hauck heavy wall thicker ringed units. Pat says .004 for trail use. I spoke to J. Simons at CPR he laughed at the .0055 and said he sets up at .0035 and I never had a chance at .0055.
XXX Where can I get feeler guage this thin. Feeler "go" "no go" seems as thou it would work fine. Also is the thickness of the material available so I could figure down to the tenths. Example .0038, .0039, .004, .0041, .0042
You guys won't beleive the bullshit info out their. Last year Millenium advised me to setup clearance at .0055. When I questioned this amount he said they set motors at this clearance all the time. Drag type motors they setup to .006 or more. Since they are experts at plating I figured they must know their stuff and see it all. Anyway ran about 2000 miles this way last year until I lost compression in one cylinder. When I pulled it apart a cylinder skirt had cracked, not off just cracked. Pat Hauck fixed the cylinder and recommended his Wiseco coated pistons. These are the made for Hauck heavy wall thicker ringed units. Pat says .004 for trail use. I spoke to J. Simons at CPR he laughed at the .0055 and said he sets up at .0035 and I never had a chance at .0055.
XXX Where can I get feeler guage this thin. Feeler "go" "no go" seems as thou it would work fine. Also is the thickness of the material available so I could figure down to the tenths. Example .0038, .0039, .004, .0041, .0042
.0035" is what I use on big bores. Is the big bore you have 72.9 or 73.9mm? If its the 73.9??, The thicker piston you speak of I can get also, its almost twice as thick as the original and has the thicker rings for a trail motor, the down side to it is its very heavy versus the original design big bore piston. You can have swain tech coat your pistons to take up some slack, you just need to give them a film thickness you need if all 3 of your cylinders are at .0055"
vipertripplexxx
New member
mac,
Don't know of any feelers that go in ten thousands of an inch. I have a set from matco tools that has multiples. For instance if I want to measure .0035" I would use a .002" and .0015" and stack them. If Don can spec out coating thickness, then you need to call him, he can get you a set that will fit in your oversized bores.
Don't know of any feelers that go in ten thousands of an inch. I have a set from matco tools that has multiples. For instance if I want to measure .0035" I would use a .002" and .0015" and stack them. If Don can spec out coating thickness, then you need to call him, he can get you a set that will fit in your oversized bores.
Mac
Member
Clearance Cylinder piston
Sorry guys I didnt want to mislead anyone. I'm running the 72.9 piston. I already ordered the cylinders repaired and ordered the pistons from Pat should arrive any day now. I wanted to verify the work and measure the clearances to ensure .004 max. It seems without expensive tools I cannot check clearance. The only feelers I can find are in .0005 increments which won't do me any good. XXX thanks for trying but half thousand won't do. Please post if anyone finds feeler down to tenths.
Sorry guys I didnt want to mislead anyone. I'm running the 72.9 piston. I already ordered the cylinders repaired and ordered the pistons from Pat should arrive any day now. I wanted to verify the work and measure the clearances to ensure .004 max. It seems without expensive tools I cannot check clearance. The only feelers I can find are in .0005 increments which won't do me any good. XXX thanks for trying but half thousand won't do. Please post if anyone finds feeler down to tenths.
Junior
New member
you can use a vernier in a pinch, especially if you measure from the bottom, provided that you haven't trimmed the intake side piston skirts when porting.