05 975 king cat issues

ac4life

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Premium Member
Jun 29, 2008
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I'm having a heck of a time diagnosing an issue with my 975. It has no 'pull.' will rev to about 7600 rpm but the power feels about like a stock 580.

The clutches are in good shape and were spotless when I put them in. New springs in primary and secondary. I have tried 4 different clutch weights and it won't rev higher even dropping from a 67s to 63s... Have also ran 70s and 68s with same results.

120/320 primary
Slp purple in secondary on lightest setting
53 degree helix

I'm trying 19/45 gearing.

Carbs all have new jets and needles. Running 360 pto and 370 mag for mains. 35 pilots. Thundercat needles on middle clip. Plugs are good color.

Engine is fresh. Had equal compression numbers on both cylinders.

Is it weird that it runs exactly the same if I switch the spark plug wires?

I don't know what my fuel pressure is.

It starts and idles great. Clutch engagement is smooth.

I bought it this summer with a 862 still in it and built it from the bulkhead up so I have no idea how the stock engine ran.

I'm hoping someone will see this that has maybe had a similar problem. I'm stumped as what to do.

Edit: running a speedwerx single and speedwerx can. I dont have a stock pipe laying around to try to know if that is part of the problem or not. Another thing to add is that my pto egts are way higher than my mag side. Probes are in y pipe. Koso gauges.
 
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ac4life

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Premium Member
Jun 29, 2008
23
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3
20181229_112933-1-1.jpg

My primary isn't shifting out but I'm not sure if it is a cause or affect.



The engine just doesn't sound quite right.

Edit: forgot elevation. Running it in fields at 5300 ft. Ride from 6-9 mostly.
 
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Idcatman3

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Nov 26, 2007
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Idaho Falls, Idaho
If you put the track on a stand and rev it, will the clutches shift out all the way?

What elevation?

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ac4life

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Premium Member
Jun 29, 2008
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I must have been editing my post while you were typing yours ��. Testing in a field at 5300. Ride 6-9 many of the same places you do. These cylinders are off of the 975 dragon you guys built! I have thought about calling your dad but didn't want to burden him. He has already helped me out a ton!

It does fully shift on a stand. The engine sounds healthy as well....
 

Idcatman3

MODERATOR: Premium Member
Staff member
Nov 26, 2007
2,157
801
113
35
Idaho Falls, Idaho
I must have been editing my post while you were typing yours ��. Testing in a field at 5300. Ride 6-9 many of the same places you do. These cylinders are off of the 975 dragon you guys built! I have thought about calling your dad but didn't want to burden him. He has already helped me out a ton!

It does fully shift on a stand. The engine sounds healthy as well....
I'm at his place today, I'll ask him what he thinks!

Sent from my VS987 using Tapatalk
 
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