CBR250RR compression tester

[vtec]

Hi all.

I've been trying to find a compression tester that will fit the CBR250RR spark plug holes. I think it needs a 10mm connection to fit. Does anyone have one that I could borrow, or point me in the right direction to buy one.

I've felt for a while now that the bike isn't quite running at 100%, and it doesn't idle like it used to, and it misses a lot down low. I've just stripped the bike down to check the valve clearances (all still within operating limits). Checked the A/F ratio screws all fine. Will strip and clean the carbs to be sure. So the last thing to check is the compression.

Another thing it could be is electronic. Either leads or rectifier, or something like that. It's only at low rpm though thankfully, and it does seem to be intermittent, although nearly all the time now it will miss at low rpm. Not good, cause I'm going to be selling up soon.

[F5 Dave]

Wander along to Motomail, they sell the adapters. Don’t be too concerned with a low reading as long as they are all somewhere near the same. Unless your tester has a long solid tube, I think it is hard to get a good seal twisting a rubber tube down a long sparkplug hole,

Just put a meter over the battery with the lights on & see what voltage it is getting at idle & when revved. If it drops below say 12.5 it is a problem. Should stay below 15. Meter from Dicks is about $10 or something silly.

[vtec]

Cheers for the advice F5 dave. I think I might be borrowing Eric's compression tester. But I'll measure the voltage. Dad's an electrician, but he doesn't touch automotive stuff for some reason, so I've got access to a voltmeter.

[FROSTY]

Dude-haul ya head off and give the lil gal a valve grind --becha thats ya problem