👍. Yep, I trying save as many as possible of the 7 abandoned bikes I brought him this spring (5 Viragos and two Suzukis). So far the ‘96 xv1100 restored nicely as well as the two Suzukis so the xv535 is next on the list. Unfortunately this ‘81 750 was too far gone for restore, but the motor was still decent and came back to life with minimal work. I hate to have to just part one out so making the motor test rig was the next best thing to do with the good motor. All the best ! Steve

Thanks ! Yep, the carb comparison one using the test rig is looking like it will be interesting for sure. I’ve got the dual carb test completed and getting ready to swap over to the single carb manifolds so hopefully in a few days I’ll be able to make the video for the comparison 👍.

Hey man ! Sorry, I just realized I said that totally wrong (I have a motor sitting in the basement I’m getting ready to take apart and just walked past it lol) the little pointy things would allow it to drip back if they are in the intake side since they are on top. Sorry about the confusing comment…I’ll edit it in just a minute. Thanks and all the best ! Steve

Thanks man 👍. Yep, it’s always interesting for me to get to play with these motors and try new things. It was interesting to see what the actual AFR was with the gages as I tuned the motor the old fashioned way “by ear” and then put the gages on to see how I did. Nice confirmation that 40 years of tuning these bikes and various other motors by ear resulted in my preferred slightly rich mixture lol. I can’t wait to finish up the carb manifold testing so I can see the results ! Thanks again and all the best ! Steve

Thank you very much for your reply my friend, I love your educational videos and you're a great teacher as well. From Gary

👍. Yep, I do get to play a bit since I have a few parts motors laying around 😃. Some of them are beyond hope and just parts at this point so I did get to make me a cool couple of piston head guys out of a blown one a couple of weeks ago lol (it’s another video out on the channel if you haven’t seen it).

Thanks man 👍. I just finished up my comparison of the dual OE carbs vs. a single carb with a manifold and the test rig did really good. The only issue I ran into was that the power steering pump puts out soooo much pressure (since I blocked off the overpressure bypass on it lol) that I spiked the initial 2000 psi pressure gage and then spiked the replacement 4000 psi gage while doing the actual testing ha,ha ! Hard to believe that the power steering pump could stall the motor, but since it’s a rotary piston pump vs. a vane pump it basically said “bring it on !” Good thing I had a 7000 psi restriction ball valve on it or I’d probably been covered in red powersteering fluid 🤣🤣🤣. Thanks again and all the best ! Steve

Hey man, I’m not 100% sure, but I believe they put those pointy shapes cast into the inside of two of the covers as those go on the intake sides of each cylinder since the cover is on angle on the head. These little pointy things would tend to collect the oil mist and allow it to drip back down vs. it all collecting up right at the cover seal and increasing the chances of oil leaking from the covers. Just another thought (I haven’t looked at where they are in a while though) would be that they would also collect the oil and then drip it back down on the rocker to help lubricate where it touches the top of the intake valves.

Hello, it actually varies quite a bit from motor to motor based on factors like the size of the carb, how closed the butterfly is at idle, and even the altitude of the location that the motor is being checked at. For multiple cylinder motors, it’s more important that the vacuum levels are the same for each cylinder, but for a single cylinder motor that comparison cannot be made. For those, I look for consistency on the vacuum reading…especially when the motor is cold and started vs. when it is warmed up as that can give an indication of leaks that are changing as parts expand and change the leak rate. Sorry I couldn’t help much, but there are so many variables in what the vacuum reading would be, it would be hard to say what a minimum number would be.