phx450 Posted February 20, 2007 Report Share Posted February 20, 2007 Anyone know of a cheap one that i can get? Pep Boys, Checker, Auto Zone, Walmart? Help! Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 21, 2007 Report Share Posted February 21, 2007 Anyone know of a cheap one that i can get? Pep Boys, Checker, Auto Zone, Walmart? Help! I don't know about Walmart, but Checker and Pep Boys ought to have a reasonably priced tester for sale. :thumbsup: Quote Link to comment Share on other sites More sharing options...
bentvalve Posted February 21, 2007 Report Share Posted February 21, 2007 sears has a really nice one w/case and many fittings for like $49 or $50 don Quote Link to comment Share on other sites More sharing options...
phx450 Posted February 21, 2007 Author Report Share Posted February 21, 2007 Any good methods for testing on twin cylinder banshee? Normally i would take out the plugs, turn the gas off, put the tester in the hole, full throttle and kick several times. Check and get a consistent reading. Is it the same way with both cylinders being done individualy? What kind of compression should i be looking at for a 4 mil cub motor, set up for gas? IF you read my thread below about this past weekend at glamis you know what I am getting at. Hopefully something simple, maybe needs new rings. I plan on pulling the head as well to take a look at the pistons. Quote Link to comment Share on other sites More sharing options...
FireHead Posted February 21, 2007 Report Share Posted February 21, 2007 Any good methods for testing on twin cylinder banshee? Normally i would take out the plugs, turn the gas off, put the tester in the hole, full throttle and kick several times. Check and get a consistent reading. Is it the same way with both cylinders being done individualy? What kind of compression should i be looking at for a 4 mil cub motor, set up for gas? IF you read my thread below about this past weekend at glamis you know what I am getting at. Hopefully something simple, maybe needs new rings. I plan on pulling the head as well to take a look at the pistons. Your method appears to be good, and yes, you do each cylinder seperately. As for what the compression should be, it really depends on your porting as well as what size domes you have in the head. One of the other guys no here that have a similair motor to yours would probably be able to better answer that question. :thumbsup: Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted February 21, 2007 Report Share Posted February 21, 2007 What kind of compression should i be looking at for a 4 mil cub motor, set up for gas? Well if you 4 mill was set up to get the max performance you can out of pump gas you should be looking for compression in the area of 150 psi. I would at least get the craftsman compression gauge. Those cheap 20 dollar gauges are not as accurate. I had the cheep o from wal mart, bought a snap on gauge and did a compression test with both gauges. Walmart one read 125/123. My snap on one read 150/150. If that little valve in the hose isnt in the very tip of the hose Then the air space between the adaptor and the little vavle are adding cc's to the combustion chamber. My cheap wal mart one had an adaptor that threaded on to the main hose. A graduated dropper and found that it added 3 cc's. I have 19cc domes but with the 3 extra cc's i was at 22cc's that would explainswhy my cheap gauge reading was low. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted February 21, 2007 Report Share Posted February 21, 2007 Don't get a cheap tester... Compression tester and torque wrenches are two tools I won't go cheap on. What size domes do you have? And, when you put the cub together, did you bother to check the squish? Quote Link to comment Share on other sites More sharing options...
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