SuperHawkins

Some of you might remember the first time I posted. I had flipped the reed-stoppers around on the PAIR valves and bolted everything back up as-is, and had major problems.

Well, I figured I had something going on with the stoppers, so I just put on some blockoff plates. Well, I have the SAME problems. I have checked for leaks on both of the plates and they are sealed up tight. I also removed the original housing, and both tubes going to that valve, and capped the valve off.

Here's my problem. The bike fires up and idles fine, and also free-revs without intake or exhaust backfires or pops. But as soon as I put the engine under load and start accelerating, I get VERY LOUD clacking sounds, very similar to the sound the carb slides make on decel, but this is a very loud and violent clack, that is through the entire rpm band. Also the motor has severe hesitation, extremely poor throttle response, and ZERO power.

This has happened twice now, both times in attempts to disable the PAIR system. I've triple-checked my work and can't find anything wrong. Is there anything I could have overlooked? Thanks guys.

Dave Wicks

Hey Brooks;

I'm thinking that there is something else that has happened. Some questions;
Was the bike..is the bike running fine with no modification on the PAIR system?? I'm thinking that you have got some hoses off.. or mixed up. The hoses that run up into air box from the carb bodies...Kind of providing chambers for the constant velocity..have you got those right?? Have you got a manual? Walk through all your lines...The pair system is down stream from anything to do with performance so even if you don't have them properly set it would not make it run badly..just lots of backfires. Have you done anything to the airbox...baffles any of that sort of thing??
..Keep posting info..togther theres lot's of skill on this site..

Take Care
Dave

SuperHawkins

The bike runs BEAUTIFULLY before I mess with PAIR. It pops a fair bit on decel, always has, but it's never affected performance and it pulls HARD, it's very tricky keeping the front tire down.

The airbox snorkel has been removed, that's the only modification. When I bought the bike, it was wrecked several times and taken apart and put back together, not 100% correctly, by the previous owner. The long carb trumpet was on the front instead of the rear and a screw was stripped.....I keep finding the guy's mistakes.

I have a manual but it doesn't go into great detail of the PAIR system. If someone has a diagram of the system, from the airbox to the valves, it'd be great.

The bike runs BEAUTIFULLY, until I disable the two valves on the cylinder heads, and the second I do that, it begins clacking horribly and pulls as if it's only running on a single cylinder. It's THAT bad.

Dave Wicks

Hey Brooks;
The clacking can be because you have messed up putting the PAIR valves in wrong...If that is so..You could be pulling exhaust gas back up and into the airbox...Do you have the lines completely blocked off from the pair system?
A common screw up with the VTR is to get the hoses mixed up of left off.. So I would start with a real look at that...Start with the vacum line to the petcock...it's not the bottom but the back...Then work all through all airbox lines....I'd put the snorkle back in if you have it...Did you do the PAIR mod along with anything else..ie; snorkle removal or k@n filter???

Dave

SuperHawkins

I installed the PAIR valves the way they came out... The blockoff plates prevent any airbox contamination, there's no exhaust gas getting back there.

None of the mods were done at the same time as disabling PAIR. The bike was tuned with the snorkel out and the tuner was able to do an awesome job with the Factory Pro kit, and I sacrifice very little in the way of useable power.

From the valves back.....the valves are in, reed-stops in place just how they came out, and both rubber gaskets are good and seated. The blockoff plates are tight and not leaking. The hoses and OE pair valve housings are off. At the check valve, on the passenger side by the airbox, both hose inlets are blocked off. That's as far as I got.

Scooberhawk

This is quite a mystery. The only thing I can think of is that you've got extra air coming into the airbox somehow, and it's making you run lean. You're saying everything is plugged up and sealed off when the block-off plates are on?

SuperHawkins

Correct.

And the last time I disabled PAIR, simply by flipping the reed-stops and that's all, it's had the exact same result. Terrible clacking/clattering noises, zero power, zero throttle response.

Scooberhawk

I'm chalking it up to supernatural forces, and challenge anyone to prove me wrong. Now bust out the Tarot cards, or do a seance or something. Or perhaps there's a spell somewhere that would unravel this bound up negative energy surrounding your PAIR mod. Hm.. Have you tried meditating on it?

SuperHawkins

I quit, this is the last time I modify this bike I swear!

Dave Wicks

Hey Brooks..
I hear the frustration...factories work hard to make things work...so our changes can bite us. But disabling PAIR should not screw up your performance. Bear with us...questions
1: When you put the PAIR back to stock does it run fine???
2: Did the "clacking" stop when you put in block off plates??
3: Have you carefully checked all your hoses??
4: Have you looked in the airbox...does it look normal in there??
If the poor performance persists with PAIR blocked off correctly or returned to stock and all your hoses are right..then something has happened to carbs. during the run up you did that may have allowed exhaust gas to come backwards..seems unlikely...
I know this is driving you nuts..but I'm still guessing you have gotten some hose pinched or on the wrong spot....Are there any other "experts" that can respond..please no more vodoo sh..Anybody live near this guy...

Keep talking to us..
Dave

SuperHawkins

Dave:

#1- Yes, when I connect PAIR back up the bike runs fine. At least it did last time, I haven't had the time to reconnect it again. I will do that within the next day and repost the effect.
#2- The clacking noise was present both when I flipped the reed stops to disable it the first time, and then the second time when I just installed the blockoff plates. It's a loud noise, very similar to the carb-slide noise, and happens constantly, in a violent fashion, during acceleration or load. I can't notice a distinct noise at idle or on a free-rev but as soon as I jump on the bike, I know something's very wrong.

#3- I've gone through the hoses and cannot find any that I missed blocking off. I only removed the two hoses leading to both pair valves, and capped off both fittings on that check valve or whatever it is, on the right side of the airbox.
#4- So far as I can tell, everything seems to be normal in the airbox. I'm stuck at work all day today but I have the weekend off which should give me ample time to find out what the hell is going on.

I tried to go through all the lines in more detail last night, but working with the halogen lamp on at 10 pm in a closed garage gets pretty tedious and sweaty. Not to mention I'm a mechanic by trade and had just worked a busy 11-8 shift, coming home to put in another 2 sweaty hours isn't my idea of a break.

Zedicus