PAIR valve blockoff

As mentioned, took my bike to the local exhaust shop on Saturday and had the cat gutted! Quite a job as it kept them busy for an hour. It's not necessary to take the entire exhaust off the bike. They managed to do it on the bike by lifting the back wheel and putting it on a step while I and another staff member held it upright.

My finding? Not that much louder at low revs however a bit more throaty which sounds nice but man the blood chilling howl when the VTech kicks in is schweet!

I haven't had it on a dyno before or after but the hp increase feel from seat to bum feels significant. It's due for a service in about 1000 km and I'll put it on a dyno then.

The bike rocks and I'm not having anything else done to it as it's smooth and goes like a bomb!

 

oh go on man , explain to us how you had them do it for you ... ?
i asked one of the local guys in town to do it for me , but he doesn't really want to do it ... wants me to wait a little longer before He cuts and shit .
I think not !!
I got the bird up to 244 On saturday , which for me is MORE than adequate , but that Cat bliksem bothers me a snitch man . I dont like having this thing on the bike , and It serves a purpose , but I dont need it . Same with the panier frames . Im in two minds of taking them off , but I dont know .

Your back tyre is not going to last much longer now with all the extra ponies ....... lol !

So you reckon it makes a difference ??
I assume then they simply cut off the bottom , close to the edge , and then yanked out the insides , and welded it back on ?? As per that other poast you showed me with the pics ?
Was it necessary to show them the pics to explain to them what you wanted ?

 

They were a bit hesitant at first, eish! They didn't know why I wanted it done as they do it on older cars with clogged up cats. They also don't really do bikes but after telling them why I want it done and showing them the pic they agreed. I recon the guys got a bit more motivated as it's a bit different than just doing cars day after day! Yip, they simply cut it open with a small angle grinder, yanked the insides out and welded the plate back again with a Teac welder. Exactly as in the pic!

The only purpose for the cat is emission control. A club buddy rides a 99 VFR and there is no cat at all! By the way, the exhaust now also runs a lot cooler and the bike runs about 5 degrees cooler as well! I've done 22 000 km since I bought it new in 2005 and know the beast pretty well! It really does make a difference! Seen race bikes with cats? I recon there's your answer!

244 is great! You guys have plenty O2 down there. I only get 235 up here. I'm keen to see if catless will have any impact but with the coppers on a bike blitz yesterday it was a bit risky to check the top end!

I usually ride without the panniers and frames as it really looks like an ou toppie bike or some on / off road bike like the GS with just the frames. I only put the frames on for trips when I actually need the panniers. The first time taking them off and putting them back on is a bit mind boggling with all the bolts and nuts but second time around only takes about 15 mins.

Also ditched the plastic rear mud guard which opens up the back wheel nicely and added a proper fibre glass hugger which I imported from France last year. The carbon look ones you can buy here simply don't work on a single swing arm. Simply too flimsy, flaps around and eventually nicks the exhaust. You realise that when you smell melting plastic!

 

mmm...Interesting .
so , having the pic around will make the difference then .. Good .
5 degrees cooler is 5 degrees cooler . klaar . How do you fit the number plaat then , or dont you ?????????!!!!!!!!if you ditch the mud guard ??

Im a little ummm... sad ? that i never bought a super , but , you know , when you wind up that V4 engine - Nothing i the WOrld sounds like it !! Cage drivers Shit themselves when the Bird comes flying past an open window at 10 thou , something I had the privelige to do several times on saturday .
we got it pretty rustig down here , the coppers are not full of nonsense .
I went onto the N@ , gave er a quick squirt , and after that I rode like a pansy . My ashirt felt Like it wanted to rip off my body - a full suit is a must at that speed eh ?
My bag openend up on my back , and tore my Golf mag to SHreds InSIDE the bag !! the wind opened the zip , and the rest mother nature and wind speed sorted out ......... Damn .... lol .

What was the charge sir ? I hope they didnt rip you off .
I must find that link quick and go back and print the photo .

 

I made the PAIR mod on Saturday and rode all day. It made a difference in the smoothness of power delivery. I don't feel the vtech surge as much so I have to pay attention the the rpms when I am cornering. But the bike is a little quicker now. Thanks for the mod info

 

Sure, the supers are quicker but u're buggered after 1 hour's ride! In any case, try the wind at 300 km/hr!

230 - 240 km/hr is pretty nice and I can doo dat all day. They can't cause the cardboard seats will grind the prostate, your arms will get tired and your hands cramp so much that you will need physio! Another thing, I often see them waiting in queues for juice at the petrol stations on the way to and from Rallies. Remember, they only have about 15L - 17L or so. I jus wave and fly by on 22L. By the time they've juiced up, I'm loong gone!

I had a smaller plate made that fits in between the two cans. I just used a small 90 degree aluminium bracket and the existing holes underneath the tail piece where the mud guard was bolted to. Looks better than dragging a billboard behind you, hidden enough and small enough to avoid that camera. Maybe you will get to 250 with a smaller plate! It’s not legal but a R250 fine for the illegal small plate is better than being caught on Candid Camera and also better than having your bike impounded for no plates

Best you get the best clobber you can afford! Besides the helmet, start from the feet up. @ 200 km/hr u're travelling at roughly 140m / sec. Just good quality armoured leathers will do! No need for a full suit as it's uncomfortable when you take a break in 32 degrees Celsius.

Oh yes, cost for gutting the cat? R300. I know that the Teac welding is very pricy. I recon it’s a good price as witnessing the process convinced me it’s not for the feint hearted.

As far as I'm concerned and my opinion of the VFR. A pretty fast and comfortable sports bike with hard luggage for travelling and that sweet V4 howl? You don't get better! Maybe the Triumph ST but I'm still not convinced! If they make a litre one day, I'll be the first to buy one! Be kind to the cage drivers as they may be your undertakers!

 

Pleasure sir!

 

Those guys on the other Forum were speaking of a leaning out of the O2 mixture as a result of taking away the Cat .

dont you think the O2 meter will do its thang and sort out the mixture ?? I mean - if this bike is so green as the guys say - surely it should sort out any fuel irregularities itself ? or would I need a Power commander to get it to do such clever things ?

I spoke to my guy this morning . Seems he HAS a bike lift - meaning , as soon as I can get the bike to him - the sooner he can get cracking . I dont want the thing going all wonky cuz i went scratching where i shouldnt have ....

 

I've read the other threads on bikersoracle.com as well. Lots of them!!!

The O2 sensor is situated before the cat and that's where the mixture is measured. An exhaust with a gutted cat provides more airflow through the pipes which = more power.

You can fit a PC at lots of RRR's which eliminates the use of O2 sensors altogether as you have to install O2 eliminators for it to work. This will smooth the power curve even more and provide a small increase in HP. It will do nothing for emissions as you eliminate the O2 sensors in any case.

But it comes at a cost and I'm not convinced it's really worthwhile. If there is a 10+% increase in HP sure, but so far I haven't seen any charts that show that sort of power increase! Probably great for racing if clipping half a sec of a lap time means the difference between 1st and 2nd! There aren't any laps where I ride never mind lap timers!

 

k , cool .
Im taking the bike Monday morning - thats If I havent fallen my Ass off in LOxton the weekend - I NEVER take off , but im considering going to Loxton for a quad race over the weekend .
Come monday afternoon - I want to see what difference the gutted Cat makes . It's got more to do with clearing out the unneccessary cobwebs , than to do with trying to make this a performance bike .
I just dont like the restriction the Cat makes - finish and Klaar .

Were you here for the Buff ?
As for the Pc - man , 1 wrong turn wth that thing , and then everything has to be reversed .

No thanks . I was considering one , but , as usual - i can never find someone reliable enough to back up his work with solid data . Same with the damn Trx - she's smoking a bit , but i now have to go to CAPE TOWN , if I want someone with a BRAIN to work on the motor .
How nice ...

 

No, I didn't go to the Buff as work and family commitments interfered as usual!

My take on the PC was spot on! I e-mailed Track Torque Motorcycles with a query on the PC. These guys are pros as they prepare race bikes for our national team and know what they talking about! Check their response:

Hello Albert, thanks for the compliment on our work place, we do our best. Your Honda is a very fine motorcycle which Honda has perfected over the years and I doubt if we at Track Torque Motor Cycles can improve upon it. The hole that you have noticed is common with all the latest motorcycles and this is due to world wide demand for noise emissions, the ECU is designed to reduce the power during the noise emission test and unfortunately cannot be altered, even a power commander cannot remove this as it only adjusts the injector timing and not the ignition timing,(there are one or two manufactures who produce ECUs that enable the timing to be altered, these are very costly and tend to be used by race teams where the rules allow their use). However fitting a PC may give you a better feeling as it can optimize the fueling at our altitude and probably help with the other things that you have altered on your bike, the cost of a PC with a dedicated map is R4500.00. Mike

So, up here where 02 is in short supply, a PC could be beneficial but words like “probably” and “may” are not convincing enough for me to spend the RRR’s

 

Shiiit , so you've done a bit more homework then .

China , I was in Loxton over the weekend - managed to Tear every ligament in my Right Knee - Jusst GREAT . That damn Quad is still gogint o be the death of me , I can Feel it .
And this coming from a guy who speaks fear into his own Heart about 2 wheel motorcycles .......

Tomorrow Im gutting the cat ... Hold thumbs . Do i leave them the Key ? Or would that be being Stupid ?

 

Soory - hold that thought - I tried throwing my Leg over to get a spin in before night falls .

My knee wont bend to get my Foot onto the Peg - so - Basically - Im stuffed ...

Got nobody else to take it there for me either .
Brilliant man , Brilliant .

 

blocked off the pair valve about a month ago now runs much smoother low through mid range. i noticed on a hot day in stop and go situation throttle jerkiness got worse,haven't had ahot day or been in heavy traffic yet to see if its truly better. all the pair valves do is dump fresh air into exhaust to clean some emissions and in doing so dump the air over the o2 sensors and create a false reading and result in richer mixture and as a result jerker throttle. disconecting the pair should give slightly better mileage as well. I think honda went to far to make the bike so green that it has effected the preformace to much so much has been written on the pair valves its hard to find the link there was a very good one on www.vfrdiscussion.com that explained the whole thing in detailout:

 

Juuuuusssssst GREAT .
I took the bike in for Cat removal - The idiot cut the bottom of that converter unit in pieces .
I have refused to go and fetch the Bike until He replaces it , his simple4 answer is then that i will sit the weekend without a bike .
I showed hm all the pics , I explained to him what needed to be done - and yet he STILL got it all wrong man . ...............
I cant believe my bad luck .
Damnit .

 

Ah man, he should be taken outside and shot!!!! :frown: :frusty: My guys were not the brightest but managed fine! I hope you get it sorted soon!

 

Good evening .

i Finally got them to sort it out .

But they removed the fairing , the front cowl , the Whole exhaust ...........

I'm telling you , I nearly died of a heart attack when I saw the Bike Lying In pieces . I called in to stop them , but by the time I got there I was too late , and the bike was lying in five thousand pieces .......

 

Farrrk, that's scary! U need trauma counceling.....? I certainly would have! Eish, did they manage to put it back together again though?

 

Yes , although , the Twit painted the bottom of the Cat box , which I didnt really want ..

Next is Gutting the Boxes ! Shiiit , I saw a guy remove the ENTIRE insides of the muffler - not funny .

Btu he Says the sound is absolutely AMAZING ...

I am thinking about doing this , but , to now go back to said @rsewipe , and ask /show him what i want THis time - he might cut the Friggin bIKE in half ........

Check This out ...........My word ....

 

I am curious as to what kind of gas milage you guys are getting after gutting the cat and either redoing the cans or with aftermarket?