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[arcticdude]

Just trying to get some ideas here.  Had a cam (Andrews EV24) put in my WG.  Since that time, if I run it hard (anything over 75 mph for any length of time) it wiil burn a qt every gas tank.  If I stay below 75, I can go 2500 miles without really using any.  What could have been done to create this kind of usage??

[RedFXR2]

I put a Andrews EV27 in my motor last FAll and haven't had any noticeable increase in oil usage.  But I didn't have any oil burning problem before the new cam, either (18k miles).

Some things to consider is how many miles are on the motor?  Did you run it fast before the new cam or maybe the cam makes it more fun to go fast so you're doing something you didn't do before?  In other words, would it have done this without the new cam (at the same speed for the same time)?

Another thing is maybe the oil isn't burning but being thrown out of the breather.  Have you seen any oil dripping onto the timing cover (assuming you have a head breather)?  Or if there's a breather hose going from the air cleaner or back plate to the ground you may not see it at all.  Evos tend to pump too much oil into the heads at high speeds (actually the oil can't drain back fast enough--tiny return hole), and most of us see this as oil dripping from the air cleaner onto the timing cone, but if you have a drip hose to the ground you wouldn't see that.  Or maybe your breather has ports leading from the heads straight to the intake of the carb (Ness Big Sucker or SE).  I use the Ness part and it helped, but didn't eliminate the situation.

I recently replaced both of my top rocker box covers due to warpage and while I was there, I installed this in the center rocker box spacers:

http://www.directparts.com/ccp/cureventplus.htm

It's supposed to finally take care of most if not all of this problem.  I haven't had the bike at speed ofr any length of time yet, but after about 70 mph for 40 miles or so, I have no oil in the breather.  So far so good.

Hope this helps.  Oil out the breather is a common problem.

[arcticdude]

Red,
Both bikes had less than 10k miles on them when the cams were done and neither had any oil consumption before the cam install.  Just to clarify, both cams are EV23's, not 24's.  I don't think that makes any difference, but just to keep everybody informed.  The weird thing is that the consumption started after the cams were installed and is essentially equal in both bikes.  I'm thinking something the tech did has caused the problem, but just haven't been able to nail it down.  There's never been anything showing outside the motor.  Both have good looking plugs, but we also don't try to run them hard because of this situation.  The thing that has me is both bikes below 75 mph do just fine, but get them over 75 and we're putting oil in them like gasoline.  I appreciate the help.  Any further thoughts???

[RedFXR2]

Leaking engine oil into the primary, maybe?  Nah, that would have made itself obvious by now, I would think.

Have the rocker boxes ever been opened and the umbrella valves replaced?  They will get old and stiff and not seal properly after some time, allowing more oil blowby into the carb.  The timing of the oil consumption with the cam jobs could be coincidence.

Hmmm.  Assuming that the only thing that kicked this off was a cam change, and no other engine components were touched, and no oil is evident on the outside of the motor (a leak), and you're sure that it's not going into the breather and then into the carb, then all I can think of is burning somehow by getting past either the valves or the rings.  If the burning only starts above 75 mph, then maybe the revs are then high enough to minimize any evidence on the plugs (thinking as I type, here).  I'll have to think about this a while.  Is the compression OK (you're sure the rings and valves are sealing properly)?

[arcticdude]

We did base gaskets on both bikes under warranty, so since we were that far we added the cams.  I've never checked compression, I'll have to look at that sometime after Cripple Creek.  Thanks for the ideas and keep 'em coming!!

[RedFXR2]

We did base gaskets on both bikes under warranty, so since we were that far we added the cams.  

The base gasket job along with the cam is a clue, at least.  There's two ways to do base gaskets--replace the rings at the same time, or leave the pistons in the cylinders by removing the wristpin circlip.  I re-ringed my Evo last Fall as part of my motor makeover, but some folks choose not to, and leave the pistons and rings undisturbed.  Actually, there's a third way--take the pistons out of the cylinders, keep the old rings and re-assemble, but I've been told that's not wise--too easy to damage the rings and that the oil scraper ring is particularly fragile.  Do you happen to know how your cylinders were handled?

By the way, you Cripple Creek guys are killing me.  I've been there in a car and can only imagine how much fun the Rockies would be on a bike.  Beautiful region of the country.  Have fun and be safe.

[arcticdude]

Well, it's been a long time, but I think the cylinders were taken off, scuffed and put back together with old/original rings- take that back- I found the original receipt- rings were done as well- at least on my DWG; but I expect the same was done on her FXDS.  Mine had 6700 miles when this was done.  I guess I should say that warranty was charged for rings and the cylinders were cross hatched.   ?

[RedFXR2]

Got this from the VTwin forum.  It was posted by one of the "Pros" on the board that has a good reputation for knowing what he's talking about.  He brings up some more obscure things that I've never thought about.

"Well with any issue on oil smoke first tihng is a comp test then a leak down, those two will allow you to know if you have a ring issue or a valve issue. If those two pass, and the heads check out. We see that many time a wrist pin bushing or a crank issue can and will cause oil usage. What amount of oil is the engine using?? If you have a extra amount of play in those two the piston can walk in the bore and cause the smoke while running and still have good compression and even leak down in a static state. Valve seals are another issue as well. Hope this was of some help. Also since it hase been apart a few times did any one check the studs?? We just saw a evo that had loose studs and the cylinder was moving only once hot. The studs had been over tq's was our finding. Replaced the studs, honed cylinders new rings and the bike has been running great."
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[killjoy]

Arcticdude,

How did you first discover the oil consumption problem? Do you normally check your oil level at each fuel stop?

[HEADPAN62]

if the timing marks are not matched up(especially on the breather gear)that may be your problem....scene it many times

[arcticdude]

I noticed the usage/consumption when we were on a trip to Yellowstone back when these were our only bikes.  Since these were our 1st two HD's, I was checking things more than normal.  Prior to the cams, they hadn't really used any oil, but after they used ALOT if run hard.  So we just started carying oil with us and checking every fuel stop.  I know that some bikes don't like to be "full", but these 2 only "use oil when run over 75 mph for a little while.  Short bursts around town and/or hot rodding them doesn't seem to use as much.  The 2 new bikes don't use any oil, no matter what speed we run.  We ran away from 2lane as we came into NC on the turns and still didn't use any on the CUSE's.  But if we'd done that on the evo's, we'd have had to gone to Ghosttown for a case of oil!