Hey guys, just wanted to get you're thoughts and experience on this one. First Harley and first issue really.

I've got an Evo FXR, 86 donk so crankcase breather that is vented to atmosphere (via a little filter under my bike)

My bike has always blown a wisp of smoke, never enough to worry me really as I'll be tearing it down in winter to freshen it all up.

Checked my oil HOT the other day, half full, decided to throw 300mls or so that was left in the bottle to top it up slightly, it didnt make too much difference on the dipstick, maybe 3/4 full (according to markers) hot.

Started it up, rode it around, and noticed at lights it was blowing a LOT more smoke. Whilst riding its not really noticable, but at lights its puffin.

First question, could this be something as simple as the oil tank being overfilled, and perhaps the lines on the dipstick are not accurate? I'm assuming no, because the oil is coming out of the exhaust and is therefor going through the engine. Its not pissing out the breather which is what I would think would happen.

 

Which leads us to either oil is getting past the rings, or past the seals.

I did a compression test to satisfy my curiousity. 150 PSI each hot, 154ish each HOT and WET. The bike is running stock cam.

From those in the know, do those readings look like it could be oil getting past the rings? A quick search on Google leads me to beleive this are pretty normal figures for a stock Evo without a cam?

 

If so, is it likely valve seals? With the way its smoking, I get the sense its sucking it past the valve seals on vacuum, or when the bike is dropping in revs after I've given it a blip.

Is it common for seals to go?

If it was only slightly and unnoticeable smoking before your oil top up and this only changed after your oil top up, I would drain some oil and go back to how it was without overthinking it, particularly in you plan on a top end freshen up in winter. The other consideration re reading the dip stick level is angle/lean of the bike

I've drained a bit of oil out, but not as much as I put in. I'll probably take it back down to half or slightly under and see how it goes.

Either way, its still going through the engine. Not so much concerned as it is annoying, and slightly embarressing haha.

The engine actually goes quite well,so  I'm reluctant to re-ring it on whim. But if its likely the seals (and probably only on one cylinder, but I still have to take my 2-1 can off so i can determine what cylinder) I wouldn't have a problem rippin that head off and replacing the seals.

 

 

EDIT: Double post

 

Would say your in the right area in regards to valve stem seal or worn guide but I would do a cylinder leak down as well before you strip it so you pin point it a bit more see what the ring seal is like aswell , and try what had been mentioned in regards
To removing a bit of oil as both my softails have different height marks on there dipsticks as one is a aftermarket type so maybe
Yours has been changed at some time in its lifetime

if the compression test is good you should do what fatbat said and don't overthink this smoking problem.
Drain the oil, and fill to correct level.
I have saw some major fuck ups on heavy machinery by people overfilling the engine oil because some dumb cunt lost a dipstick and thought any old dipstick would do.
I have no experience on the EVO engines .
What colour is the smoke? Blue White or Black?

Blue white smoke.

That comp level is about what I get on my 86 Evo so your in the ballpark. I would be thinking valve stem seals, or if you run the oil breather into the carb then blowby.

Fair enough perthog. The oil is getting into the combustion chamber somehow so how do you pin point where its coming from?
Does the bike smoke more when you start it up in the morning John?
Sounds like its been smoking for a while so it should last until the summer ends , let us know the details when you pull it apart
My money is on the valves but I know nothing about Evo motors

So that's smoke from 3 weeks ago before u topped it up ?
It would breath more out of the breather ,mist , drip etc if it had worn rings /bore/glazed bore /broken rings hi comp mtr bigger ring gaps for forg piston s.etc
That's oil entering the combustion cycle eka worn guides ,valve stem seals
As you said engine vacuum is at its highest at idle and light cruise And the oil is getting pulled in
What's the plugs like ? No matter what you do , do a leak down before you strip it engine at running temp
Over filling won't cause it to go out the breather , normal spew out of the tank cap on softails anyway .
Normally if it's coming out the breather only after it's been sitting it's oil leaking past the check ball in the oil pump
But that's another story I believe your on the money in regards to guides /seals if comp and leak down. Are
Pretty good you could give try changing the valve stem seals with the heads on , if not. I would
Freshen from cases up as if just pull the heads you may create a base gasket leak witch u won't be happy about later .

At the risk of sounding like a dumb cunt, whats the difference between a compression test and a leak down test perthog?

A leak down test is when you put compressed air into a cylinder at tdc at engine running temp so you can
See what leakage you are getting Example blow by it will go past the rings and into crankcase,
Inlet valve leaks out the intake manifold/carb tb Or if it's exhaust valve out the exhaust
Your basically checking the sealing side Of rings to bore , valves to valve seats ,
This won't tell you what the stem seals or guides are like though but doing this is part of any engine
Condition diagnosis , just like a comp test but with a different kind of tool

ok mate. got it. cheers.  sort of. I think.

If its me and the bike was a keeper I wouldn'nt fuck around I would pull it down and get the heads reconditioned and have the barrels bored and fit new pistons and ring

and go fuck yeah

Yep, and cash to do it properly, got a different kind of ring purchase soon. Whether I refurb those heads or get new S&S or S.E heads, pistons, maybe barrels, and new cam.

Or if I could, whole new S&S donk.

I'm happy to rebuild the engine myself but obviously have to outsource the head work and bore.

Yep. Need to pull my finger out and finish this kwaka 750 build and sell it. That'll go nicely towards a new donk.

Fuck it, thinking I might just get this expedited, does anyone know a good place to send the heads to?

Ideally Id like to send the heads and barrels to someone, they reco/fix up the heads, bore out the barrel (if it can be, not sure on size yet), sell me some new high compression slugs that matches up with everything and an Andrews EV46 Cam and some gaskets, send it back to me to bolt it all up.

Wishful thinking? Recommendations?

If your taking the heads off, then you may as well hone the jugs and fit new rings (no need to remove the pistons)
- The oil seals are a piece of cake to replace if you have a spring compressor.
- likewise get a good shop to do the hone (one that uses torque plates) and does Evo jugs.
- rings are easy as to fit plus its good experience.
- you could just shave the heads 50-70 tho to raise the compression a bump.

Mind you with the static comp being around 150 your rings and jugs could very well be fine (thats the reading I get on my 86 Evo as well)

Yeah I've got no dramas with actually rebuilding it, its just the headwork.

The only spanner in the works is that I wanted to do a whole bunch of stuff in winter, including higher compression to better utilise an EV46 cam over an EV27.

If I'm going to tear it all down to the base gaskets, I'll just do it all properly and throw the higher comp pistons etc in. I'm hearing you on shaving the heads down though, be good to have a chat to someone in the know. I'll be needing a gasket kit, headwork, bore, maybe pistons, cam etc, and would be good if there was a 1 stop shop.

I've got a leak down tool coming so that should shed further light on it.

If I can get away with just seals I'll probably do that, if its actually the guides, and the heads need to be done, I'll get the rest done at the same time and save myself going through 2 full gasket kits in a couple of months.

 

Doing the call around this morning, haven't come across a headshop that's got torque plates...so any reputable recommondations would be appreciated. I've heard Hood Engineering in Adelaide is pretty good.
 

Im in ACT, and Pulfords has just closed up shop and auctioned his entire workshop off.

Bad timing really, but no real hassle to send the gear somewhere who'll do it properly.