Have been tinkering with a 97 EG fro a few months now. Have the bike like I want it and riding it a good bit more. It would run bad on occasion when I first got it. It would run like it was on 1 cyl. Pulled spark plugs and the rear one was all carboned up. I mean covered. Thru a set of plugs in everything fine for 150 or so miles. The bike acted up again coming in from a 250 mi day ride. Ck'd plugs Rear solid black Frt plug some black but not to bad. Changed plugs and plug wires. I changed plugs 2 more time at various mi. As time has gone on the distance I ride has become less and less needing to change plugs. I got the bike to an Indy for his thoughts on it, He test rode it YUP something is wrong he says. He went to looking at the plugs ( same as above) We put a new set in and he went to cking for air leaks and adj. the carb some. It was running good and he test rode again, it acted up Real Bad in less than 3 mi. He came back and used some brake clean we had looking for a vac. leak. See if the motor rpm would change. It didn't seem to change much till he hosed down the rear cyl where the head meets the jug It died almost immediately. Did this 2 more time same results. He says blown head gasket. ??? Caught me a little off guard What do y'all think Thanks for your time WP

 

While it seems strange to me that brake cleaner would kill the engine with how combustable it is, If there is a repeatable effect from sparying at the head gasket (dying or revving up) i would have to agree there is a leak in the head gasket. FWIW When i blew my first head gasket there was no mistake about it. BIG BANG, fireball out the side of the bike, loud sound of sucking air right in the cylinder, and feeling of "running on one cylinder" permanently. Not every failure is the same, but did you have any of those symptoms?

 

Also, head gaskets on these bikes are very easy to blow if you dont let the motor warm up fully before riding hard.

 

Yep, head gasket would be my diagnosis too. Although a compression and leakdown test is in order too.

 

Non chlorinated stuff will kill an engine at idle I use it to track intake leaks , no mess & cleans the area nicely .

Evo head gaskets you can hear going 90 % of the time kinda of a squeaky piff sound & at an idle just run hand around the mating area you will feel it blowing out when warm .

 

Gotcha. I had always heard of using starter fluid to check intake manifold leaks which makes it rev up, so the killing the engine confused me. Learn something new everyday! (unfortunately i forget 2-3 things every day too)

I heard mine going, but did not know what the squeaky sound was, when it really blew this was the result

 

The big bang is what I'd thought I'd got as well Doesn't seem to be the case Ummm LOL things that make ya go Ummm. It was Non Clorinated brake clean as mentioned in one of these post Thanks WP

 

Had red that and heard it before I don't how the PO did things I love the ol bike but this working on it this much is gettting a bit old LOL

We Gonna Fix It Yet BAG Thanks WP

 

Asked the Indy about those tests today He smiled and said D you know alot more about cars than I do but ya know after what we did last night. The Head Has got to come Off LOL Dang It Thanks WP

 

My suggestion would be to do james or cometic gaskets on the whole top end. The harley paper base gaskets suck, they will leak and push out and give the cylinder more play making the head gasket more prone to failure. I rebuilt 2 times then used james in the third, she was good to go (still warming it up plenty of course).