Could a dented pipe cause low rpm

[kmg]

As the title states. Brothers sled the pipe is dented and it will only ever pull 7900 rpm.. the dent happened years ago now and honestly can't remember if it immediately lost the rpm or not. But it's definitely been a few years that it's only pulled 7900 as well. My first thought was wore out clutching so he bought an Indy Dan kit for this year, we shall see.

Dent is not huge but it's there


We only get to ride 1 week a year out west so it's hard to trouble shoot issues.

 

[BeartoothBaron]

Do you have any pictures of the dent? It could be causing issues, but it'd have to be pretty big or in just the wrong spot to have a significant effect. If it's smaller than a couple inches across and less than 1/2" or so deep, I'd say not. It wouldn't hurt to swap pipes just to be sure, but I'd dig through other potential culprits before I spent any money on another pipe.

 

[sportfire]

Got one behind the bumper on my 13, seems to run fine. Also 1-2 times a year so I'm not too concerned.

Clean EX valves and holes?

 

[czimpel]

A couple things come to mind for me.

Compression check - I would be looking for close to 120lbs on the gauge that I use - Leak down is better if you have that option.
Plugs
Exhaust valves
Clutching

 

[kmg]

Do you have any pictures of the dent? It could be causing issues, but it'd have to be pretty big or in just the wrong spot to have a significant effect. If it's smaller than a couple inches across and less than 1/2" or so deep, I'd say not. It wouldn't hurt to swap pipes just to be sure, but I'd dig through other potential culprits before I spent any money on another pipe.

Dent is about that size yes. No pictures at the moment.

Got one behind the bumper on my 13, seems to run fine. Also 1-2 times a year so I'm not too concerned.

Clean EX valves and holes?

Same spot and yes cleaned valves.

A couple things come to mind for me.

Compression check - I would be looking for close to 120lbs on the gauge that I use - Leak down is better if you have that option.
Plugs
Exhaust valves
Clutching

Changes plugs every year
Exhaust valves clean
Trying new clutching this year

As for a leak down I should have added it's about 4 % on one side 10% on the other. So he plans on rebuilding anyway.. but it's acted like this for probably close to 750+ miles... So I'm torn as to whether it would have lasted this long if that's the issue and it's been that bad for this long?? In fact it's acted like this longer then that.. as when I originally bought the sled (before selling to brother) I had to run 58 gram weights for 8-10k. I rebuilt it once with RKTek pistons and turned oil pump up and it had zero effect on rpm. Still struggling to ever pull even 8100 way back then.

Is it possible I turned the oil pump up too much back 8 years ago?

 

[kmg]

Update:

Sled always ran a little funky at home in MN and also wouldn't pull over 7900. And engine light on for O2 sensor even with a new sensor.

He put on a new to him pipe tonight.. (he figured give it a whirl) engine light turned off and sled runs absolutely perfect pulling 8250.

 

[sportfire]

Awesome.

 

[IDspud]

We’ve undented a few using plumbing test plugs and a regulator to pump air in slowly, massage around dent with a dead blow and it’ll pop right back out most times.

Obviously too much air will make you rethink where your test plugs are pointed.