CPI questions

[charoy]

Bought a bike back in march it was ported and has CPI pipes. Also 33mm flat slides. i have no bottom end (in the power band it's a rocket)it was suggested to me to change pipes. Hence why i am here. what is the difference in big bore and small bore pipes. Again they were on the bike when i bought it.

 

Thanks

[dragbanshee]

Not positive where else, but right after the flange area they are larger diameter. If you want low end switch to T5s, great low end in my opinion, I just switched from T5s to CPIs and like them. I did lose some low end but the mid and top make up for it. Kind of all depends on your mods though.

[SAVAGE420]

I agree with what dragbanshee said. Also im pretty sure the slinger tubes are a lil larger diameter also on the BB pipes.

Edited July 21, 2009 by savage420

[FireHead]

Here's the deal:

 

1.) There are big bore pipes and small bore pipes.

2.) There are big flange and small flange pipes.

3.) There are big bore, small flange pipes.

4.) There are small bore, big flange pipes.

 

.......... you can have any combo of these things.

 

Y'all only need small flange, small bore pipes.

[charoy]

Here's the deal:

 

1.) There are big bore pipes and small bore pipes.

2.) There are big flange and small flange pipes.

3.) There are big bore, small flange pipes.

4.) There are small bore, big flange pipes.

 

.......... you can have any combo of these things.

 

Y'all only need small flange, small bore pipes.

 

The pic above is the pipes as they sit on my bike are they bb

[Wildcardracing]

You can also look to timing advance or increased compression to bring some low end to it if they haven't allready been done. Depending on the portwork, switching pipes may not help a lot. You might want to find if someone local has a set of T-5's for you to try before you trade out of your CPI's. I've been very successful getting an extremely smooth/broad midrange power band with CPI inframes, so I would tend to think the majority of the issue is in the porting. It may be more drag orientated. Too much blowdown timing and/or lack of transfer time area compared to exhaust time area and the motor will be peaky no matter what.

 

**EDIT** The pipes in your pic are small bore from what I can tell

Edited July 21, 2009 by slobanshee06

[J-Madd]

The pic above is the pipes as they sit on my bike are they bb

 

 

No.

[Snopczynski]

T5 does the same job as a cpi, the cpi just does it better. I personally would never trade cpi's out for a T5.

[06specialedition]

I run cpi's and absolutly love them!

[Burt Reynolds]

I had the same prob when i put my cpi's on,+4 timing solved my problem