Thread: Loss of RPM
07-26-2007, 05:46 AM #1
Loss of RPM
Have lost RPM from 8150 to say 7800/7900 re-shimed SC all ok. Have a silicon intake cooler this time water in boost hoses ( not good ) . Has this happed to others and also what was your loss of rpm. been up all night but can only find the Intercooler problem !! other than that all looks ok, even checked prop and liner all OK.
For any help Steve
Rotax SC wheel
Riva intake pipe and filter
Riva Skat 15/19 SS wear ring
Riva exhaust Mod box
07-26-2007, 07:29 AM #2
hi steve,iam still down as well 7850 but its better than the 7450 i was turning the other day ,my speeds are back .i think iam still slightley over on the oil but not much at all now just over middle.
ive been watching other peoples rpms and this seems normal around now maybe it is heat "u wouldnt think it with this weather "
07-26-2007, 07:41 AM #3
Mine is down at 7720 and speed at 65.1, it seems to be heat related. I am going to check my impeller pitch and supercharger during my next service to confirm this is actually heat related or not..... water is in the 90's here in Tampa.
Didnt you guys get a lot of flooding out there in the UK????
07-26-2007, 07:50 AM #4
Plenty of water over here.
I can only put my loss of rpm down to the water in the intercooler always been a steady 8150 all year ?
Left out in the open prop good liner good no leaks so not sure ?
07-26-2007, 08:40 AM #5
I was running 8120-8140 at MB III and now in Dallas I'm at 7920, 90-95 degrees and fairly high humidity, for Dallas. I've searched my ski over, replaced the wear ring, went back to my stock air intake. It just feels slow, I've been told it's the heat.
07-26-2007, 08:45 AM #6
07-26-2007, 08:49 AM #7
It's amazing how much the heat and humidity can affect our skis. Thats why i love having the adjustable venturi nozzles. When the temps come up i just pop in a bigger ring to get the R's up.
07-26-2007, 09:37 AM #8
07-26-2007, 10:14 AM #9
Don't think this is a heat problem as steved and rior1 are both in the uk...and it's far from hot at the moment!!..steved try disconecting the hose that goes to the t/b and go ride with the seat off have a look to see if any water comes out under load?.How long has the xs been fitted for? only thr rotax i/c that seems to last the distance
07-26-2007, 10:16 AM #10
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