1.3 rocker arms

playnotwork

New member
what am i doing wrong. fitted rocker arms on both the inlet and outlet ports, valve lash at 0.003. Taken to track, no improvement on lap time or apparent power of the engines.
engines are gx200 standard 0.065 skimmed off the head.
help appreciated cheers
 
1.3s are not an automatic improvement. Too many variables. All they are doing is increasing the amount of valve lift throughout the duration of the cam. If the cam was not the restrictive part of the build, they wont help. If the carb is way too small or the exhaust or the ports are restrictive, 1.3s will show no improvement. Remember, adding these will put extra strain and wear on the entire valve train as well as the cam. Make sure they didn't cause the valve springs to coil bind or the retainer to hit the guide or the valves to hit the piston.
 

steve baker

New member
Honda Engineering is pretty darn good at engine development with regards to matching the intake and camshaft system. You might want to explore upstream of the valve events in the complete induction system before adding more lift and duration at the valve. As the world knows Honda is the benchmark in this industry!

Steve
 

playnotwork

New member
what am i doing wrong. fitted rocker arms on both the inlet and outlet ports, valve lash at 0.003. Taken to track, no improvement on lap time or apparent power of the engines.
engines are gx200 standard 0.065 skimmed off the head.
help appreciated cheers

forgot to mention that i did have these running well with just the 1.3 rockers on the outlet,( then messed aroind) put back to standard and then 1.3 rockers on both and then back to rockers on the outlet only and can not get the earlier performance back. only the lash could be different or could th springs have gone off so quickly
 

W5R

New member
If you put the 1.3 rockers in and didnt change springs at all, you probably wore out the springs using those rockers. Put fresh springs back in it. Carb setup, cam timing, ignition timing and compression can all affect how the engine runs with the 1.3 rockers....usually you have to change all of the above to get the best results when adding more lift like you did with the 1.3 rockers
 

playnotwork

New member
Finally got around to putting new springs in with 1.3 rockers inlet and outlet. turning over just avoid coil bind so lobes appear to be ok. noticed when setting lash to 2 and 3 thou that the rockers after a coulple of rotions of the crank skew to the right, sitting off centre on the valve retainer and appear to slightly open the valves reducing compression. set the lash to 4 and 8 thou. went for a run and still no gain grr is this to much lash
 
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