Exhaust nipple for gas tester

Has anyone found a hollowed bolt or nipple or something that would allow a hose to be hooked up to the individual exhaust pipes for a gas tester? My bolts are 6mm.

I was planning on doing a dyno run and tuning my carbs while idling using their air/fuel meter. however, I cannot find anything that would allow me to hook up a hose to the individual pipe.

 

No help here? The guy at the shop today that told me that Yamaha made a special connector for this. Does anyone have any info? Anyone ever take their bike to the dyno?

The guy at the dyno told me he couldn't get a good reading on my bike because the exhuast baffle was too close to the end of the pipe, and fresh air would taint the readings. So has anyone ever used a gas tester? If so - how?

 

Yes, there is a special manifold with 4 braided steel lines that connect to 4 nipples that screw into your header pipes. The manifold has valves on each line to isolate the cylinders that you're not adjusting. It's the only way to properly adjust each individual carburetor fuel screw. The shop I used to work at now just samples the tailpipe & looks for a change when turning each fuel screw. Works ok but not as accurate as isolating each cylinder individually. Check with your local Yamaha dealers for the manifold.
Good luck,
Tom

 

Here's some info from a Yamaha Technical Bulletin that I found.
Not much to go on, but some info!

 

Why not just thread a piece of 6mm brass tubing, in a similar fashion as the syncronization nipples for some types of bikes? You could make up a set of four or just one and pop it into the hole of the cylinder your tuning.

 

Thread a piece of hollow brass? That is a good idea, and I would just slip a rubber hose over the other end?

Thanks Robert, you are a genius!

 

Not even close, but thank you. I just had one of the machinists at the base tool up a set for my sync gauges to do my FZR.

 

Did you use hollow brass stock, or solid, and drill it out? Where did you get it?

 

I purchased hollow stock (8mm OD with 2mm ID) and had the fellow turn it down for me. Most well stocked material or metal supply houses will carry it or can order it for you. You can use just about any metal you would like but steel tends to be harder to turn and thread. For the application, brass is a good choice. It will seal rather well, especially when heated. I'll post some pictures of my toys here in a bit. I've got to go take pictures of my bikes right now anyway (got the back patio almost cleared. I took a lunch break and here I am, what dedication)!

 

What bolt size went in your exhaust? Mine are 6mm. I do not have a lathe, so I may be out of luck. I also don't have a tap and die set! Bummer.

Would you be interested in letting me buy a set of four from you?

 

I guess I could try to have some more made up. Let me contact my source and I'll get back to you. My bolts are a 6mm as well.