Testing newly rebuilt engine on the bench ? Yes ? No ? How do you do it ? Or not

My case was similar. I had to do some cutting/ welding repairs on the ex-racebike frame so the motor was already out and the frame was bare. The bike was a parts bike that I had for 10 years and was disassembled partially never thinking it would ever see the road again, so I never heard the motor run properly. It had stock CV's with no airbox so I heard it pop and sputter a bit before taking it apart, but I wanted to hear it idle before I started investing a lot of time on the motor. I had other motors I could put together if I had to. I sold the carbs at some point and was going to modify the intakes to use slide carbs. I knew there would be some testing I was going to need to do and the frame was nowhere near ready.

I made the stand as a wheel barrow so I could wheel the motor around in the basement. One single rod goes through the motor mounts at the lower front portion of the engine. This allow me to tip the motor forward to access the bottom. I put a metal pan on it to catch drips etc. That was handy. I could change the oil by using a shallow pan. To make the motor level, I just let ithe rear end rest on a block of wood.

For inline fours, the engine will be stable during acceleration, but deceleration might might try to tip it forward so you have to lock the back end down. I just used that bungie you see in the photos. It was more than enough and the motor seemed very stable.

I made the stand from wood re-claimed from other projects so the whole thing came together pretty quickly. I had a lot of the hardware from other deck projects etc. Probably took a couple hours to assemble, and maybe another hour or two to shape the pan and main rod holder. Most of the metal parts are the framework of wheels for cabinets etc. I pulled them out of the dumpster at work, but you can find other substitutes for that.

It was much nicer doing work without the frame around the motor for cleaning gasket material etc. on the clutch cover and valve cover. I also had to fix some parts on the trans cover. Access for cleaning the grease buildup was very nice.

Now that the project is over, it has become the defacto battery maintenance area, plus it holds a bunch of other junk too.



I had a post with the use-whatever-I-have build, but I think the photos are gone now.

hardrockminer wrote: Here is a photo of the Kawasaki engine test area for Z1 engines from back in the day.

Never seen that picture before. Does anybody know more about this setup? I don’t recognize that instrumentation in the exhaust area - old school A/F measurements maybe?

This gives me an idea, old untitled frames can be cut down and used for engine mounts
I happen to have untitled frames for a 650 and a 1000 so before I scrap them I will have to make a couple

ayeckley wrote:

hardrockminer wrote: Here is a photo of the Kawasaki engine test area for Z1 engines from back in the day.

Never seen that picture before. Does anybody know more about this setup? I don’t recognize that instrumentation in the exhaust area - old school A/F measurements maybe?

I was wondering why the machines are labeled in English.

bluej58 wrote: This gives me an idea, old untitled frames can be cut down and used for engine mounts
I happen to have untitled frames for a 650 and a 1000 so before I scrap them I will have to make a couple

Sounds to me like you have a couple race bikes to build.

I have a titled 77-1000 frame and most of the parts at this point for a build,
even though it will be a bit sportier then my current ride my racing days are over

Nothing wrong with testing a "new" engine on a well built test stand. I'd make sure to have the full exhaust mounted and use a proven fuel system (carbs that you know are functioning and tuned properly). I completely understand why you might want to do this.

One thing that needs to be said, and this is from my days of building nutty screaming racing pushrod V-8's, is that if you are starting a new engine with NEW cams and cam followers (on our KZ bikes, that would be shim under buckets, or new rockers on a 16V Suzuki GS. Adjusting shims bearing directly on cams don't appreciably wear unless something really bad happens, and then they must be discarded anyway), it is highly recommended you run the engine for at least 20 minutes at no less than 2000 rpm (for adequate oil flow / volume) and use an oil or oil additive(s) for break in of flat tappet type valve trains, all to properly break in the new camshaft and followers. You must be sure not to overheat the engine and /or oil (keeping a big fan blowing cool air over the engine works well enough). When breaking in new pistons and rings, using standard mineral oils vs synthetics is usually recommended for proper ring seating and sealing during initial break in. But just following the piston ring manufacturer's advice about break in procedure and oil type is what you really should (always) do.

After the initial break in, dump the still warm oil and look at it carefully. Some like to examine the filter; even as far as cutting it apart and examining with a magnifying glass and sweeping a strong magnet over it. You are looking for any abnormal metallic residue. Bigger chunks are a sign of impending mechanical doom. If all is good, add a new filter and run the same type of regular oil as used for break in for the first 300 miles or so (you don't need the additives again). Then you can switch to synthetics if you want...

hardrockminer wrote: Here is a photo of the Kawasaki engine test area for Z1 engines from back in the day.

Looks like they did the testing from deep within the bowels of an old battleship.....