cpi inframes how to tell big bore are small bore

[jimmy3]

Hey guys i used the search and did not find anything?? Does any body know the measurements on a small bore inframe cpi pipe?? Mine is 1 inch od do i have small bore or big bore i think they are small but dont know for sure Thanks Jimmy

[theshee]

Big bores should have big bore flanges.

[dajogejr]

Call CPI..

 

Not true, Keil...

I have Big Bore Shearers but small flange for my 10 mil cub...

 

Very little difference between the two...

They are made in several flange sizes, cub (stock) bigger cheetah, DM...probably a few more.

[theshee]

really... did you have to have them special made from CPI. I thought RDZ and shearer were about the only ones that put small bore flanges on big bore pipes.. Good to know!

[dajogejr]

really... did you have to have them special made from CPI. I thought RDZ and shearer were about the only ones that put small bore flanges on big bore pipes.. Good to know!

 

 

reason I know is because I bought pipes from strokerace that he thought were for a cub. they were too small for his DM motor, but too big for my cub. I sold them to my buddy Rob who has either a 14 or 16 mil cheetah...fit perfect.

So... I know there are at least three flange sizes, stock to 14 mil cubs all take the same, small flange (same size as stock, I don't know off hand the measurement, 46mm maybe??)

 

When I split a weld in my new shearers (warrantied no problem) I borrowed a set of big bore, small flange CPI Stinger pipes off my buddy...same thing no biggie...

[Snopczynski]

The 1" is the "big bore"pipe. The 7/8" stinger outlet is the small bore pipes.

[dajogejr]

The 1" is the "big bore"pipe. The 7/8" stinger outlet is the small bore pipes.

 

Snop...I think the header pipe after the flange might be a hair bigger, I"m not 100% positive though...

[Snopczynski]

You may be right, but easiest way to tell that I know of is to check the stinger outlet size.

Edited December 26, 2007 by Snopczynski

[jayzx10r]

The 1" is the "big bore"pipe. The 7/8" stinger outlet is the small bore pipes.

Is your measurement ID or OD? The thread starter measured his as 1" OD...that may translate into 7/8ths" ID. I'd like to know the proper measurement as well because I've found some used CPIs that are 1"OD and the owner doesn't know if they are SM or BB...

Neither do I!!

Edited December 26, 2007 by jayzx750

[Snopczynski]

I think it is id, you need to contact cpi to find out exactly, or have someone on here check theirs.

[jayboy]

I think it is id, you need to contact cpi to find out exactly, or have someone on here check theirs.

 

I know t thread is really old..how ever picked up set of inframes for my bike..they were used, and couldnt get real answer as to how to tell apart from big or small... called CPI measure stinger welded to expansion chamber..OD 1" small bore... 1"1/8 is big bore..no other diff according to cpi...

[DwnSouth]

If you have access to a known set of small bores it's very easy to tell them apart. Where the header pipe joins the stinger pipe is clearly bigger on big bores. No need to measure anything. My buddy has a set and that's the only diff we see.

[jayboy]

If you have access to a known set of small bores it's very easy to tell them apart. Where the header pipe joins the stinger pipe is clearly bigger on big bores. No need to measure anything. My buddy has a set and that's the only diff we see.

 

good point...these are small bore...had no access to any others...and several people i asked couldnt answer or would measure there own....oh well, just sharing what i learned.... they do run much better than the r2"s that were on my cub.