SuzukiSavage.com - 100km tear down after 684cc. Too much Carbon?

Moarpower

Senior Member

Offline

SuzukiSavage.com
Rocks!

Posts: 331

100km tear down after 684cc. Too much Carbon?
04/24/23 at 19:42:27

Hey guys.
So as I posted earlier, I have the new cam and bigger piston but the cylinder base gasket failed. So while waiting for the OEM replacement I ton the head off. I noticed quite a a large amount of carbon and heat already present on the piston and valves. This may be totally normal but I just wanted to make sure. I am still dialing in the carb

I've done just under 100kms in this engine and as it is my first build, I was hoping for some guidance. The spark plug look pretty good.

Back to top

Compress_20230425_124153_3304.jpg

IP Logged

Moarpower Senior Member Offline SuzukiSavage.com Rocks! Posts: 331	Re: 100km tear down after 684cc. Too much Carbon? Reply #1 - 04/24/23 at 19:43:12 Here are the valves. Intakes quite black but exhaust is rather clean still
Back to top	Compress_20230425_124153_3082.jpg IP Logged

Gary_in_NJ Serious Thumper Offline LS650 Cafe Racer Posts: 2633 Amongst the Twisty Roads	Re: 100km tear down after 684cc. Too much Carbon? Reply #2 - 04/25/23 at 06:51:55 Actually, looks good to me. I'd say the bike is properly jetted and runs well.
Back to top	A life-time student of motorcycling. LS650 Cafe, DRZ400SM, FZ6N, SV650S, CB900C, Ducati ST2, CB550F-SS My LS650=> http://suzukisavage.com/yabb2.2/Attachments/Left.JPG IP Logged

Moarpower Senior Member Offline SuzukiSavage.com Rocks! Posts: 331	Re: 100km tear down after 684cc. Too much Carbon? Reply #3 - 04/25/23 at 16:07:43 Gary_in_NJ wrote on 04/25/23 at 06:51:55: Actually, looks good to me. I'd say the bike is properly jetted and runs well. Ok thanks. This is my first time rebuilding a bike so I'm still learning
Back to top	IP Logged

DragBikeMike

Serious Thumper

Offline

SuzukiSavage.com
Rocks!

Posts: 4408
Honolulu

Re: 100km tear down after 684cc. Too much Carbon?
Reply #4 - 04/26/23 at 12:36:18

I know you only have about 100 kilometers on it, but how do you like the Wossner piston so far? What can you tell us about it? By any chance did you test the compression after you assembled it. How much pressure did it pump?

At only 100 kilometers yours just doesn't have enough time on it to tell much but it seems OK to me. One area of concern is the nice clean ring all the way around the piston. You are using the stock MLS gasket so it must be overhanging the bore a bit. That could be a problem. Have you measured the clearance between the piston and the head gasket?

This is a picture of a 97mm Wiseco pop-top after about 6000 miles of operation. It was running pretty good and the air/fuel was set up with a wide band instrument. I'm sure it's not perfect but as I said, it was running good and the fuel/air mixture was very close. Should give you an idea of what to expect.

Back to top

Approx_6000_miles.jpg

Knowledge is power.

IP Logged

Dreanimal

YaBB Newbies

Offline

SuzukiSavage.com
Rocks!

Posts: 21

Re: 100km tear down after 684cc. Too much Carbon?
Reply #5 - 04/26/23 at 15:45:10

I'm no savage expert but I've got quite a bit of experience with engines. The uneven carbon build up on the piston is a bit of a red flag from what I know. Do a wet and dry compression test as well as leak-down to look for ring issues.

What kind of conditions were these 100km, one freeway cruise or a lot of low speed around-town trips?

Did you install new rings with this kit and gap them properly?

What does the Savage use for an oil control ring?

Any oil consumption or fuel in the oil?

Add a picture of the spark plug, if you put a fresh one in and do a few
WOT pulls it will tell you a lot.

Back to top

IP Logged

Moarpower

Senior Member

Offline

SuzukiSavage.com
Rocks!

Posts: 331

Re: 100km tear down after 684cc. Too much Carbon?
Reply #6 - 04/26/23 at 20:17:19

DragBikeMike wrote on 04/26/23 at 12:36:18:

I know you only have about 100 kilometers on it, but how do you like the Wossner piston so far? What can you tell us about it? By any chance did you test the compression after you assembled it. How much pressure did it pump?

At only 100 kilometers yours just doesn't have enough time on it to tell much but it seems OK to me. One area of concern is the nice clean ring all the way around the piston. You are using the stock MLS gasket so it must be overhanging the bore a bit. That could be a problem. Have you measured the clearance between the piston and the head gasket?

This is a picture of a 97mm Wiseco pop-top after about 6000 miles of operation. It was running pretty good and the air/fuel was set up with a wide band instrument. I'm sure it's not perfect but as I said, it was running good and the fuel/air mixture was very close. Should give you an idea of what to expect.

Thanks Mike.
It was mostly just easy riding around 70kmph.

I am using the stock head gasket so there is a bit of overhang. I was not able to get one made to fit here in Australia for a reasonable price.
I wonder if there is a safe way for me to trim the gasket.

It was running awesome. The wossner was great.

Back to top

IP Logged

Moarpower

Senior Member

Offline

SuzukiSavage.com
Rocks!

Posts: 331

Re: 100km tear down after 684cc. Too much Carbon?
Reply #7 - 04/26/23 at 20:23:06

Dreanimal wrote on 04/26/23 at 15:45:10:

I'm no savage expert but I've got quite a bit of experience with engines. The uneven carbon build up on the piston is a bit of a red flag from what I know. Do a wet and dry compression test as well as leak-down to look for ring issues.

What kind of conditions were these 100km, one freeway cruise or a lot of low speed around-town trips?

Did you install new rings with this kit and gap them properly?

What does the Savage use for an oil control ring?

Any oil consumption or fuel in the oil?

Add a picture of the spark plug, if you put a fresh one in and do a few
WOT pulls it will tell you a lot.

Thanks. All just easy riding at or below 70kmph with a few WOT pulls.

The new rings came with the piston and I gapped to spec. The uneven build up I believe is due to the stock head gasket overhanging about 2 or 3mm. I need to find an oversized gasket but having no luck.

I will do a comp test when I reassemble.

Back to top

IP Logged