Installed the springs using the FMF Spring Puller (Great tool) and the broke during my first moto at the track. The hook parts on the ends are the weak points. I found one spring dangling from my case with the opposite hook completely missing.
From looking at the OEM diagrams for your 2004 Honda CR125 I can see that it actually does not use this style O-Ring Set up. It uses a larger exhaust seal ring. It does use springs but FMF does not have a kit with just the springs for your bike.
I would recommend ordering the Honda OEM Seal and Springs.
You would need: Honda OEM #91304-KZ4-L11 (seal), Honda OEM #18332-KS7-830 (springs). You would want to order 1 seal and 2 springs.
[ Here is a link to the page that shows the seal at the cylinder head: http://www.motosport.com/dirtbike/oem-parts/HONDA/2004/CR125/CYLINDER-HEAD-%28'04%29 ]
I have a 2000 yz250 and you can see the smoke sometimes comes out and leaks a bit out of where the pipe meets the cylinder. i was wondering if this would drag down hp?? I have weak springs and no o rings
Actually ... no. Once I received the kit I found that the springs are too long and will not keep the pipe in place. I had to reuse the old springs until I can get some replacements that fit.
The O-rings work great.