Topic: Digital Bore Guage need help to pick out a good one

[chewbacca5000]

I wish to buy a digital bore gauge so I can check my own cylinders for diameter, roundness and tapper.  I want to be able to check to see if rebores are needed, or to check work from my local machine shop.  If anyone has any experience with these gauges and can recommend a good one I'd appreciate it.  Thanks!

[Kong]

Mitutoyo.  You can't go wrong.  Buy used, there are lots of them on the market.

[chewbacca5000]

Thanks Kong!  Will this one fit the bill?

http://www.ebay.com/itm/MITUTOYO-DIGITAL-HOLTEST-CASE-468-219-1-DIV-0002-NICE-CONDITION-NR-/320827155971?pt=LH_DefaultDomain_0&hash=item4ab2c9e603

[754]

 That only covers a 1 inch range..6-7.. got to do a lot to justify the price.

 Why do you prefer digital  vs dial ?? lot less to go wrong with dial..

The one shown is better for round concentric bores, for cylinders a bore guage is better for checking taper..simply run it up and down the bore.  For checking out of round, simple rotate it, in a few spots..

[dave500]

buy a digital vernier caliper and a set of telescoping bore guages.

[Toxic]

I'm a tool geek and I couldn't justify spending the kind of money it takes to buy a good one.
I took my barrels to a local machinist  and his gauge was $1500.  For the $60 he charged it was well worth it.

If I were building allot of bikes then it would be worth it.

[dave500]

like toxic said,if you only want these guages for a one off,dont bother,a digital vernier caliper is a handy tool though,,bearing journals/cam lobes/piston skirts etc,combined with an average set of telescoping bore gauges and itll all work ok,,just finesse in use is the key,if theyll gather dust its not much point?

[scunny]

I just take mine to a local recon place, let the kind man measure them, chew the fat, shake hands and it's measured. have to try and convert his imperial to metric tho.

[70CB750]

Check Enco for reasonably priced machinist tools or Grizzly.

[chewbacca5000]

Thanks guys for all the advice.  I think I will pass on the bore gauge for now.  Not only are these tool expensive, but they are difficult for someone like me who does not not have experience with them.

Dave,  I am trying your advice with the telescoping tools and digital caliper and was having a hard time getting consistent measurements.  I got a piece of flat angle aluminum across the top of the cylinder and that is improving things considerably.  I am still getting some that are way off. I might try using a speed square and adding a black line or scribing a line to make sure the telescoping tool is perfectly square in both directions.

Any other tip to use this tool better would be helpful.  I am just looking for ball park figures to determine bore size.  Thanks!

[754]

 The telescoping guage is not real easy to use, takes a lot of time and effort to measure a cylinder bore.
 Use a dial bore guage in the middle of the bore, rotate in a few spots.. look for runout..then pull up and down..look for taper .. if you see 3 thou.. you need a rebore.. all that without breaking out a mic or even looking at the actual size.

[chewbacca5000]

The telescoping guage is not real easy to use, takes a lot of time and effort to measure a cylinder bore.
 Use a dial bore guage in the middle of the bore, rotate in a few spots.. look for runout..then pull up and down..look for taper .. if you see 3 thou.. you need a rebore.. all that without breaking out a mic or even looking at the actual size.

Thanks 754!  So putting the guage in the middle of the cylinder and rotating 360 degrees I should not see 3 thou.  Pulling up and down checks tapper.

Will this dial guage work for what your are talking about?

http://www.ebay.com/itm/2-6-DIAL-INDICATOR-BORE-GAGE-0005-GAUGE-/300527104142?pt=LH_DefaultDomain_0&hash=item45f8cfb08e

Thanks!

[754]

That is what you need, even a cheapo should tell you what you need to know.

 The 3 thou I threw out there may exceed the weasr spec on a Honda cylinder.. just saying that with a bore guage you can quickly see excessive wear..without looking at the actual size.
 if you use telescoping guage set it front to rear and lock then turn 90 degrees..if you cant stand it up straight.. you got wear..