Thread: Still Chasing RMP loss
08-12-2007, 09:11 AM #1
Still Chasing RMP loss
I have two 1300s built the same, both have always run the same rpm and the same speed. Now all of a sudden one of them lost 50-60 rpm and about 1 mph.
Thing I have already checked include.
I have changed head gasket
Checked the reeds - OK
Checked and adjusted power valves - OK
Tried a different EFI controller - no change
Pulled pump and checked bearing - OK
New plugs side gapped and indexed
Checked Compression - still the same
Anybody have any ideas?
2003 1300 GPR 75.9 @ 7090
Unported and Injected.
Fercho's Package, and 3 deg key
Head by Lowell Horning.
Rossnemos Sonic Boom TB Mod.
Jims FF Mod Plate & Trim Tabs.
14/23 Solas DF Frecho Spec from Impros.
Riva 1200 Grate.
08-12-2007, 09:43 PM #2
Check to see if the pump shoes bolts are tight, If any of them have come loose at top speed the pressure will push the shoe down and create drag. Also check the ride plate bolts and trim tabs. Also check the pump shoe seal job make sure no sealer has blown out of the pump shoe. I have seen a few that have blown out at the rear of the shoe between the shoe and transom plate.
08-13-2007, 06:03 AM #3
All look good . I'm going to check the jetworks gasket next to make sure it's not leaking, and letting to much water into the water box. Then if I have to the keyway.
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