Questions about cored/gutted cat & mufflers....??

[Werloc]

I was given a cored stock cat, and mufflers. Can I use these without doing anything else and be safe? Will this change my mixture, to lean or to rich? Will the bike run OK? How about the O2 sensor? I was told it would be fine, but I just want to be sure.

Thanks

[kingsnake1650]

I have cored mufflers and my bike runs great. no popping or anything. Next I plan on coring out my cat, and doing the airbox mod.
Want to sell you uncored cat after you get you cored one installed?

[Werloc]

I'll let you know. Let me try the cored stuff first and see how it sounds and runs. So your saying that if I put the cored cat and mufflers on, everything will be OK? I will also be doing the airbox mod, but not until the end of next week. I just want to be sure about this before I put them on. I'm very old school (mostly 2 stroke), and don't know the new ECU, O2, sensor, mapping, etc.

[Werloc]

Originally Posted by kingsnake1650

I have cored mufflers and my bike runs great. no popping or anything. Next I plan on coring out my cat, and doing the airbox mod.
Want to sell you uncored cat after you get you cored one installed?

Why would you want the stock if you like it cored? Just wondering. I may need to hold on to them to pass state inspection.

[kingsnake1650]

Originally Posted by Werloc

Why would you want the stock if you like it cored? Just wondering. I may need to hold on to them to pass state inspection.

I have not cored my stock cat...yet. I did the muffler and have had no ill effect. Net I plan on doing the cat and the air box. I would like to have an extra stock cat so that if I run into trouble I can revert to stock.

[GMP]

Basically, the system will trim itself to acheive the same 14.7/1 ratio when in the closed loop part of the map, which is where you ride most of the time. Where it could get lean is in the fixed open loop part, like higher RPM/larger throttle openings. Every bike is a bit different.

What are you doing about the EXUP valve?

Start saving coin and watching ebay for a DP ECU, its the best thing you can do for the bike. You don't realize how lean the stock bike is until you ride it corrected.

[Werloc]

Originally Posted by GMP

Basically, the system will trim itself to acheive the same 14.7/1 ratio when in the closed loop part of the map, which is where you ride most of the time. Where it could get lean is in the fixed open loop part, like higher RPM/larger throttle openings. Every bike is a bit different.

What are you doing about the EXUP valve?

Start saving coin and watching ebay for a DP ECU, its the best thing you can do for the bike. You don't realize how lean the stock bike is until you ride it corrected.

I was going to leave it. Should I disconnect it?

[GMP]

Why bother with an open cat and open cans if you are going to let the ECU close the flapper just when things are starting to get rolling? You can't just disconnect it, you need to limit the travel of the servo so it does not throw a code.

[Werloc]

That's why I'm asking. I know nothing about this stuff. I'm old school, and haven't tuned, or wrenched on any bikes since the early 90's. Don't know squat about all this new electronic controled units. Give me an old carbed engine, and I'm at home. Then I can tune with sound, and plug readings.

[GMP]

If you can work a small piece of 1/16" sheet aluminum with a hacksaw, drill, Dremel, and file, and cut two 6mm bolts you can fab a limiter plate I designed. It mounts in front of the servo between the motor and pully with two longer bolts and a few washers. If you want to do this PM me and I can fax you a copy of the template I made. If your not in a hurry, I'll be removing my servo when I install Leos this fall/winter (hopefully fall) and will no longer need mine.