Hi!

I will need to fit something to the Stuart Taylor Locoblade (yes, I reported I bought it some days ago, see the "Thinking of moving on" thread saying thanks to everyone for your help!) as in Spain we have emissions tested every year for every car under the sun.

I'm totally clueless about the options available, either as a permanent fitting or as a MOT-only botch add-on (I'm happy with either, the cheaper the better).

This morning I've been told about some full kit for that which includes electronics and stuff (sounds strange to me) being manufactured by Fisher, apparently very expensive (around £400??) so not very appealing.

I suppose I could fit the original bike cat cv by modifying it to suit the Stuart Taylor mainfold exhaust? Would I need to do something to the engine other than changing the can bit of the exhaust? What is that electronics box business about? Firing? Sorry my total lack of tech vocabulary (and skills for that matter), your patience is appreciated.

Any other options? Advantages and disadvantages of having that fitted permanently? Anyone else around that has to go through full emission test every year?

Many thanks.

Hi Alez
For most bike engines running with carbs (rather than fuel injection) to pass the current emmisions levels, they need to be fitted with a closed loop lambda system and a cat. The closed loop system basically consists of an electronic box which is fed a signal from a lambda sensor situated in the exhaust, and an engine temperature sender. At tickover speeds the box sends a signal to two solenoid valves which are plumbed into the inlet manifold, these valves open and allow small amounts of air into the engine, which lean out the air/fuel mixture enough to pass emmisions. This is the kit which Fisher and others sell for £400.
I have this system permanently fitted to my car (except the cat which i have now removed) but interestingly at SVA i had to disable the air bleeds to obtain the required emmisions levels and so in effect passed the emmisions with CAT ONLY. I think it may depend on the engine and is pot luck. But if i had my time again i would attempt the test with just a cat fitted, these can be bought brand new for about £100.
Hope this helps,it's hard to explain in text.

Alan.

]Originally posted by Alez
Hi!

I will need to fit something to the Stuart Taylor Locoblade (yes, I reported I bought it some days ago, see the "Thinking of moving on" thread saying thanks to everyone for your help!) as in Spain we have emissions tested every year for every car under the sun.

I'm totally clueless about the options available, either as a permanent fitting or as a MOT-only botch add-on (I'm happy with either, the cheaper the better).

This morning I've been told about some full kit for that which includes electronics and stuff (sounds strange to me) being manufactured by Fisher, apparently very expensive (around £400??) so not very appealing.

I suppose I could fit the original bike cat cv by modifying it to suit the Stuart Taylor mainfold exhaust? Would I need to do something to the engine other than changing the can bit of the exhaust? What is that electronics box business about? Firing? Sorry my total lack of tech vocabulary (and skills for that matter), your patience is appreciated.

Any other options? Advantages and disadvantages of having that fitted permanently? Anyone else around that has to go through full emission test every year?

Many thanks.

Hi Alan,

That was very helpful indeed, and very clear. In fact I'll be taking a printout of your post to Spain so I don't forget how it goes when I need to sort it out.

When you say a cat would be £100 brand new, is that one to fit the dimensions of a Locost (narrower diameter thn bike's I think) or that is the original bike one which needs further modification in order to be adapted?

I've just taken a look at you image archive, there is a pic of your exhaust with some bit between the end of the mainfold tube and the end can bit, is that the cat cv, coupled to a normal bike can or coupled to a Locost can (narrower diameter)? Is it bolted or welded?

Many thanks for your help.

Hi Alez
yes i bought the cat from Tiger sportscars, i think it is 100mm diameter, it comes fitted into a stainless steel tube with a cone welded to one end, and a loose cone for the other end should you need it, i welded the loose cone to the other end and also welded on a flange with 4 bolt holes, the standard bike can is welded to the other cone, i can unbolt this lot in minutes and fit my regular carbon race can. Iv'e tried to upload a sketch but dunno if it will work.
The other good thing about this setup is the car becomes whisper quiet.

Alan.



i]Originally posted by Alez
Hi Alan,

That was very helpful indeed, and very clear. In fact I'll be taking a printout of your post to Spain so I don't forget how it goes when I need to sort it out.

When you say a cat would be £100 brand new, is that one to fit the dimensions of a Locost (narrower diameter thn bike's I think) or that is the original bike one which needs further modification in order to be adapted?

I've just taken a look at you image archive, there is a pic of your exhaust with some bit between the end of the mainfold tube and the end can bit, is that the cat cv, coupled to a normal bike can or coupled to a Locost can (narrower diameter)? Is it bolted or welded?

Many thanks for your help.

Nope, cant upload the sketch here, but its in my photo section.

Alex, just to clear up any confusion, the bikes themselves don't have a Cat fitted, so any Cat you buy will be an aftermarket one.
As Wadders mentioned, the £400 buys you electronics and valves as well as the Cat itself. Ive never had to run a Cat system on mine so am not an expert but it sounds like the air valves only activate at idle or low engine speeds, so if the Spanish test is done at higher engine RPM then I assume you'd be likely to pass with just a Cat, but it does depend on the tests they do.

Chris

Many thanks guys. It's kind of stupid that the exact same engine needs a cat if it's used in a car when it doesn't if it's used in a bike! Oh well! I'll be taking your valuable input to Spain, I recall being told that the test is done at 2k5 which is funny because that's significant for a car but close to idle for our nice BECs..

Cheers,

Alex