Compression tester

[headshrink]

I was thinking about adding an inexpensive compression testor to my collection. Can anyone make recommendations for one that will fit/work well with our bike?

[Racer x]

This is the first thing I found on E bay.

http://cgi.ebay.com/ebaymotors/OTC-5...#ht_3856wt_939

OTC is good and that is a good price . The main thing you want to look for is how the end that screws into the sparkplug hole is attached to the hose. If the one you find has one hose and little screw on ends DON'T buy it. Get one like the photo that has a separate hose for each size plug. The problem is IF you screw it in tight enough to seal then go to remove it and the hose unscrews leaving the end in the spark plug hole you are in trouble . You may have to pull the head to get it out(ask me how I know).

Some times the hole is not drilled exactly on center of the tube. When the end goes in it the adapter will jam against the side and stick real tight. I have the sides of my tester ground down because of this.

[headshrink]

Thanks.

I was hoping a $20 kit from Autozone would do, but I should have known better. If this is what you recommend, I'll trust you on it..... sure is cheaper than some I saw on motorcycle pages.

[headshrink]

I noticed the same product, for about the same price ($49) on Amazon. There is also a leak-down tester for $20 more.

There is also a compression tester on Harbor Freight for ($25). They also have a cheapo leak-down tester, but it doesn't have a 10mm adapter. I know HF can really be hit or miss.... is this kind of tool something that needs to be higher quality than HF usually sells?

If I steered away from HF, would it be worth while to go with the leak-down tester instead ($61)? This is new territory for me, so I'm reading about all this anew. Guide me, oh wise ones.... What are your recommendations.

[Racer x]

I like HF as long as the tip dose not unscrew from the hose you should be OK but it is a get what you pay for thing.Good tools are an investment. I would not get the leak down tester. Yopu probubly won't need that.
When checking a 250 ninja the pressure should be kinda even and above 160psi. With 120psi they won't even fire starting fluid. With new 13 to 1 pistons I have had as much as 230 psi

[headshrink]

The reason for my interest in the LDT was, from what I read, it looked easy to use (I have a nice air compressor). But the PRIMARY thing that appealed to me was that it pinpoints where the leak is (ring, valve, head gasket), basically a fancier compression tester..... Am I understanding this correctly?

So are you steering me toward the CT because you don't think I need to spend the extra $$, or because you think it is the proper tool for the job?

For reference here is the HF compression tester: http://www.harborfreight.com/quick-c...ter-95187.html

And here is the Amazon Leak Down Tester: http://www.amazon.com/OTC-5609-Cylin...=pd_sim_auto_1

[Racer x]

A LDT is not easy top use . And you still need a compression tester first. Let's say you run a compression test one is 180 one is 120. The 120 is a bad thing. So you use a LDT to figure out the problem. It will show a 50% loss of pressure .and you feel air coming out of the carb. That indicates the intake valves.You have to pull the head.If you did not have the LDT .you would still pull the head to fix it.A LDT is nice but I rarly use them and never have needed it for th e ninja engine

[headshrink]

Just ordered the HF compression tool....

[headshrink]

Results are in this thread: http://www.ninjette.org/forums/showt...856#post310856

[rockNroll]

You can use some compression set ups as leak down testers too. It would depend on what kind of set up you got.

I'm looking at the HF link you posted. If the nipples on the three hoses are proper to fit into the end of the air hose on your compressor, you can remove the schrader valve from the hose, put it to the spark plug hole, put the cylinder at TDC then put your air to it. Don't go blasting it with 100psi, you'll just push the piston down and rotate the engine. You need to regulate the air down. Listen to where the air escapes most.