The International CBX Owners Association

well larry , you "helped" more than i ....at least you drank more beer

That's a moot point Dan......

Joking aside, it was Prestons attention to detail that really impressed me. I can be "anal" at times at perfectionism, but Preston was right there with me.......

Nice Guy too.......

Well, the drinking beer part is very, very important so you probably deserve more of the credit than you realize.

Preston has many talents. Have you ever seen him giving a how-to-deal-with-your-husband's-motorcycle-addiction speeches to ladies?

Thought there might be some stuff here to make it worth another look-see.

Well, it has been awhile since I posted my question about compression on my 81 CBX. Since adjusting the valves, doing carbs etc.. etc.. and putting about 300 miles on it, the compession is now between 135-146psi. Adjusting the valves brought them way up. Had two that were too tight so this explained that low compression. I have a 79 with an 80 motor, 16k miles, and it has compression of 131-141psi. I am currently baffled by the ebayer that claims his silver 79 now on ebay, has 175 psi in all 6 cylinders. Has anyone ever had this kind of compression on a stock CBX? 175psi in each?? I am re-learning a lot about these bikes and have collected four of them 79, 80, 81 and 82. The 80 and 81 came from the original owners and are 100% original/stock.

The method on how you check compression and what instrument you use may have a lot to do with the number you end up with. The run-of-the-mill meters may vary quite a bit. The manual spec says 171PSI +/- 14 PSI
But even that is a conversion from the old metric spec of 12 +/- 1 kg/sqcm and does not quite jive , if you use the correct factors. I have two PSI gauges that are off by at least 10% from each other. If you squirt some oil in the cyclinders and check your compression, you may get a higher reading.

You are correct about different methods of checking compression. I check it with all plugs removed, throttle fully open, engine slightly warm (for obvious reasons), air fiter in, air box lid installed, cranking until gauge needle stops/peaks. Regardless of how the compression is checked, I have never heard of or witnessed a compression of 175 psi and this is the original question. I don't care what method you use, I dont "think" you will ever get 175 psi - in all cylinders??? Not happening!! Unless you have a gauge that is stuck on 175psi....

"Just" did a compression test with a warm engine that needs to be blown out a bit...156-165psi were my readings...