Removing the catalytic convertors?

Hi all, anyone removed the cats on a FI model? as I understand, this will not light the FI light up and will sound better and give a bit more power or so I'm told by a car mechanic. Just thinking aloud at the moment but food for thought!

I can't see there being any noticeable gains Mick?

Bugger it then!  

Mick we don't remove them, but members do remove there use though. They do it when looking for a better louder sound by belting a pointed rod up the center of the pipes which put a hole in the two plates that are half way up the pipes or another way of describing it, at the top section of the rear muffler.

Hi Mick, if you remove the cat it should help the engine breathe easier, it is surprising how restrictive they are and heavy, if you do that and fit more of a free breathing exhaust have a look at Mr I,s section on EFI boosting, also an exhaust that would look OK and is easy to de-restrict are the shotgun style ones off Harley's, will be doing an instruct able on these when we get back as I have a couple of these knocking about in the spares caravan and they are reasonably cheap to buy.

Hi, I like the standard look but a bit more of a fruity sound, I have already spiked the exhaust but stopped at the cats as I'm a coward, bike seems better for it I have to say. I will try to man up and poke a stick through the cats and try to remove them completely when I get chance. I will have a mooch at the harley pipes though! Thanks for the reply.

spoke to a pal of mine down at the shooting range and he said if the lambda sensor is behind the cat it could/should trigger a fault code but looked a bit confused when I told him that after market zoists don't have cats and don't trigger the FI light. he also said the best way to remove the cat is with a masonary drill as they are made of ceramic! you learn something new every day  

There'll be no problems with the FI light if you remove the cat's, they're after the lambda sensors and the sensors only read the unburnt fuel/air ratio and send signals back to the ecu to lean things out accordingly, I'm not sure on noise improvement? but I still don't think you'll notice any performance gains by removing them but I'll be interested in your findings  

Cheers Sim, that's if I grow a pair and decide to give them a battering! Still scared!

Hi Mick,


it sounds like you are getting to 'crunch point' .... either 'rod the cat' (so to speak) or look at aftermarket pipes. (Or stay as you are).


I think the straight-shots look good on cruisers.
   Yam

a length of 8 or 10mm thread sharpen the end with a angle grinder knock it down through all the plates in exhaust can be done nice and slowly while being in total control best to use a club hammer because of the weight of hammer you don't have to wack it just slowly bang it through thread is the best thing to use as if it feels stuck you can use mole grips to turn it out (like a screw) all so it's cheap to bye and normally comes in meter lengths from all the usual DIY shops I've done it to 3/4 bikes I have had in the past without any problems

mick9264 wrote:

Hi, I like the standard look but a bit more of a fruity sound, I have already spiked the exhaust but stopped at the cats as I'm a coward, bike seems better for it I have to say. I will try to man up and poke a stick through the cats and try to remove them completely when I get chance. I will have a mooch at the harley pipes though! Thanks for the  reply.

Hi, I stopped at the cats as I wasn't sure if it would make a difference, I used a 20mm drawn steel bar which I sharpened in my lathe and it breezed through the plates with very little effort. I was going to drill the cats out but wanted to hear off someone who had already done it in case I made a bollocks of my pipes. She sounds better for the mod especially under load and is still quiet on tickover but with a deeper tone. Cheers!