Well, as some of you may or may not know, imma 81 sportster owner. 1000cc. Runs great, doesnt leak (no i aint kidding..haha) Looks great, was cheap and i love it!..but here's my newest rant..

Its using oil. Doesnt seem to be burning a whole hell of a lot? i put about 1000 miles on it since august 8th, and i've used about a qt so far... i keep a spare cuz everyone said to keep one cuz it'd leak it out.. but as i stated, it does not leak..it burns it somewhere.. (stopped my leak so i figured that'd cause another issue..haha) As for the oil burning, not sure where or when its burning it.. It doesnt smoke at startup, and i cant seeeee the smoke when i'm riding (or when i let someone else ride it to see if i can notice the smoke) so i dunno if its just burning so very little that i cant see it or what. i re-routed the breather so it doesnt feed into the carb, i put an auxilary breather filter on the case vent. The Plugs dont have carbon deposits on em from oil, just typical looking plugs.. SO i dunno WTF is up or where this oil is going, but it gets lower on the stick as time goes on and miles add up. Compression is 150 in each cylinder, as for oil rings..i got no clue what they look like, cuz i didnt tear it apart, nor do i really want to unless i get told i should. Something else someone said was that the ironheads were known for the valve guides going bad in them, and once replaced, typical oil consumption problems ceased to exist. (i was also advised to put the valve seal kit in too, helps with future problems of this nature)

Also, oil looks great. no chips, flakes or metalic specs in it. Thats why i'm puzzled as to WHERE its goin and whats goin on!??!?!?! imma pull primary drain plug and see if its WAY over full..just incase its blowing it out into the primary, but i dont think (hope anyhow..) that its goin into there.


What do yinz guys have to say? Thanks much!!

 

If you bike is a 1981 model then it does not have the transfer valve between the crankcase and the primary. So there is no way oil can be getting blown into the primary/trans like older models which have the transfer valve can do.

Your compression is 150lbs. That is excellent!
Are both cylinders within 10 psi of each other? If so, that is even better.
The plugs are not oily? That is good.
If the guides were worn...it would smoke.
If the oil rings were worn...it would smoke.

You have no symptoms of the engine using oil.
The oil level is dropping because of the miles you have ridden.
There is the breather tube beneath the bike. This originates at the crankcase breather sitting atop the oil pump. There is a small continuous oil mist traveling out this tube as the engine is running. Yet you cannot see this mist but it is there.
So, some of the oil is going out the breather tube.
Some is getting burned up. Not enough to see the smoke, but nonetheless some is getting burned.

My oil Sportster uses oil just like yours does. I change the oil at no less than every 500 miles. That is much too frequent, but it should be done every 1000 miles.
Just enjoy riding the bike and keep the oil tank topped off.
The faster you ride the faster the oil level is going to drop, so keep checking it.
I'd say you have nothing at all wrong with your engine, so stop worrying.
pg

 

Well, thanks PG, glad to hear someone else has same issue. haha. and yes both Cylinders are both at 150 on the money..i used 3 diff guages to verify cuz i thought the first guage was messed up, used the second guage and got the exact same readings, 150 on both, i then used the 3rd guage and got identicle readings. i used each guage 3 times. so a total of 9 readings per cylinder, all giving me 150 so i was rather satisfied with that.

i had no idea about that little breather at bottom of motor, atop the oil pump, imma check it out. As you stated with the faster i ride, the more i'll burn..i DID notice that. one day we rode for 3 hours at about 65mph. got home, noticed that the oil level was a little lower than most days, put it back into its par range, and then rode again the next day. This time just cruising speed. 45, to 55 tops, with the occasional Loud N Rowdy Take off. After getting home and checking oil, it was at its normal location, just as it is everytime. SO i gotta good idea as to how much it likes to use per day or Per tank. (peanut tank..) so when i fill up, i also check my oil. and make sure my blinker fluid is full too of course

I guess most ppl would say i'm **** about things..but i been a mechanic for a long time, and its just my nature to wander, worry, and try to prevent major mechanical failure. Everyone who knows i own an ironhead, says thats deff the bike for me cuz it needs attention n such from time to time and they know ill give it the attention it needs. (like just today i noticed a little detonation, prolly cuz its hot as ***** here today) so i'm currently trying to find an adjustable timing light to make sure its in the range it oughta be in.

But i do appreciate the input PG, Thanks again!

PS, know where to find the plastic see thru plug that goes inplace of the timing inspection plug? lol

 

Did you hold the throttle wide open when you did the compression check?
That is the proper way to do it. But the important thing is that both cylinders are the same.
If one was drastically lower that would point to worn valves and/or seats in that cylinder. Yours seems stable.

The plastic plug can be found at most indy shops I would think, or they can order it.
But you too can order it from this place yourself.
OEM part # 96295-65 for $5.57 @
http://www.narleychoppers.com

pg

 

yes WOT during comp check. as for pretty much everything else also i believe (atleast thats how i've always done everything else. lol) Imma check at the West Penn Choppers (local shop here in PA) tomorrow. i was just there today but i forgot to ask them. also check with my fellow iron riders to see if they got one. I even thoughta bout turning one outta some some Round lexan we have at work.. i could easly thread it to match the plug!

Thanks PG

 

<I even thoughta bout turning one outta some some Round lexan we have at work.. i could easly thread it to match the plug!>

That will work! I made mine out of a piece of Plexiglas rod turned on my South Bend and then threaded it on the lathe as well.
All you must do is polish both ends of the rod to be able to see the slash mark.
Getting the slash mark (represents the front piston) anywhere within the hole is close enough on the timing. Centered is perfect, but anywhere in the hole is plenty close enough.
pg

 

Cool good deal! ill see what i can round up at work and keep ya posted. after posting earlier i went for a nice relaxing cruise. Wow the damn bugs were bad tonight. like, seriously felt like i was riding in rain! Thank god for Safety glasses. haha

Something else i noticed, that aint major, but caught my eye. i was polishing off the boot burn from my womans boot, and noticed my rear cyl exhaust pipe chrome is staring to pit? or something. only in ONE spot, and not anywhere else on the exhuast. neither front nor rear. so i was like AHHH CRAP! lol i think someone put el-cheapo drags on it..no surprise though. PO was a hack artist. I think i may end up wrapping them if it comes down to it but if not, i wanna get a set of GOOD drag pipes and then put the lolli's in em. Only reason i'd keep the chrome idea is cuz i got underglows up under the tank and damn, it looks sweet at night time! CHicks dig it! :-D haha

 

This is the one that was running up into the air cleaner. Older models use the fitting at the 6:00 position; 79-on use the new fitting at the 11:00 position.

You can use both to improve crankcase ventilation. The fitting at 6:00 is 1/8 NPT. Remove the plug, insert a hose fitting for 3/8" ID, run the hose to the back of the bike, along the frame and muffler bracket.

You will notice the engine sounds like it is running more freely, possibly a little noisier, may feel like you got a few extra horses.

 

prolly aint gonna vent it also .i already got top one (at 11 postition) vented through and auxilary filter. Les stuff runnin all over the place. Does it really make that much of a diff in motor performance at all? like i know it wont be drastic, but will it make it noticeable? Regardless of what it'd do for the feel, i still aint gonna molest it. just hate the idea of stuff runnin all over the place. haha.

 

You say your engine does not leak oil.
I assume you think this because you can see no oil externally.
Fair enough.
It enough oil is coming out the breather to an extent that after only a few hundred miles the level in down enough to concern you, how is it that there is no visible evidence of this?
Where is your breather routed to?
Does it look like oil has been "pouring" out there?
A common complaint on HD bikes of any model is oil mess from the breather. Enough mess to look terrible, and annoy, but not cause a concern regarding oil loss.
How is it you are presumed to have the opposite?
As in, no mess, but the oil is still coming out there, and enough for an oil loss concern issue.
Use your common sense. If you can see no evidence whatsoever of oil on the outside of the engine, especially near the breather, then it is going somewhere else.
And failing the very unlikely scenario that is is in the transmission, that somewhere else is out the exhaust pipe.