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1978 R100/7 recommended Spark Plug ? / Recommended Oil - Synthetic? Regular? Brand?

SCBuckeye

New member
I am in Ohio, where currently it is frigid and cold, and am wondering what some of you think about:

Spark Plugs

What is the current number(s), Brand(s) that are most recommended for reliability for spark plugs?

Do people use/recommend various heat ranges? If so, under what circumstances do I use which one?

Oil

Also what oils are most recommended?

Is is OK to switch completely to synthetic.

I just got back into the BMW family, and way back when (late 70's, early 80's) on the /5 bikes, the consensus opinion was to avoid any synthetics, but I suspect their apprehensions were unfounded simply because synthetics were new on the scene.

However, now, with the latest advances in synthetic technology I would guess that some have tried and now swear by some form of synthetic oil. What brand/viscosity?

BTW, I have read the oil report, and found it not very helpful. I suspect that some of you have some valued experiential knowledge.

What do you suggest for both of these questions?
 
I have a '79 R100RT with about 40K miles and use synthetic, but I have oil seeping from the oil pan even though I have a new gasket. Maybe I installed it incorrectly, but I'm switching back to dino oil before I pull the pan to see if that'll fix the problem. I have no problem changing the oil more frequently when using non-synthetic oil if need be.
 
The standard plug for the R100/7 is a Bosch W6DC (non resistor). In NGK, the BP6ES would be used.
 
NGK's are available and cheap

The standard plug for the R100/7 is a Bosch W6DC (non resistor). In NGK, the BP6ES would be used.

Good luck finding the Bosch plug. i run either the NGK W6DC or a NGK W7DC in a couple of bikes, my slash 7 seems to enjoy a 6 whereas the 72 slash 5 likes the 7 range. So I go to just about any auto parts store and buy a box of 4. A box of 6's and a box of 7's, I think they are in the $2.75 range per plug. A common problem on most older airheads is the right hand cylinder runs a bit rich due to the crankcase breather hose hanging out on the right side and feeding a steady supply of oil mist into the cylinder. It is not that bad but does create a richer condition on the right side. Usually around 5,000 miles I replace just the right side plug, then the next time both of them. Good reason to just buy a box of four.

Oil: I use the prescribed dino oil of the 70's. Spectro 20w-50. Works fine as far as I am concerned, got 105,000 on the slash 7, she is happy, price of the oil is reasonable, I do roughly 3,000 miles changes and every other change a filter. However, that does not always work. My last oil change cycle was about 2,700 on oil only, then I went about 4,000+ before then next one, because they were all hwy miles the oil still looked fine. Oil is not something I would fudge on, I am somewhat anal on making those regular changes but don't feel bad if they are just a bunch of hwy miles between a change.
kurt
 
Good luck finding the Bosch plug. i run either the NGK W6DC or a NGK W7DC in a couple of bikes,

NGK doesn't make a W6DC...might be a typo there. I haven't bought plugs in a while, but I thought you could get Bosch plugs at a dealer and also remember that NAPA might be able to get them as well. It's important to inspect the plugs themselves, not just the box labels, to ensure the part number doesn't have an "R" in the number, such as WR6DC. The "R" indicates it's a resistor plug, which is generally what you don't need.
 
Got my sparks missed up

Got my figures missed up, in the NGK I think it is BP6HS or maybe ES and a BP7HS or ES, again don't have my plug boxes handy.
And regarding a fouled plug or a rich plug, yes, there is a difference, oily or just a bit darker but dry, big difference. I don't have oily plugs, to be clear the right side is simply a bit richer and therefore darker shade of tan.
kurt
 
As for oil, my mechanic uses Mobil 1 15/50 synthetic. He uses that in all of his airheads, and recommends to his customers to do the same.

So that's what I use. I have also used Golden Spectro 20/50, and also I think I also even used Honda branded oil at one point.

Now, I just use the Mobil 1.
 
Not gonna touch the oil question... :bolt
but you can get all the Bosch plugs for most (all?) airheads for very reasonable prices right here: http://www.euromotoelectrics.com/category-s/40.htm

Plenty of other service and upgrade goodies there also. :thumb

I have no connection to the store or it's owner other than I have bought great stuff there at great prices and the owner has been extremely helpful especially on electrical stuff which is his stock in trade.
 
Thanks to all of you!!

Hey, thanks to all of you.

You guys are the best!!

I have gotten some great ideas on the best places to buy stuff - in this case, spark plugs!

JimmyLee
 
I'm not an engineer nor do I play one on television but I have slept at a Holiday Inn Express. A Texaco engineer told me one time that oil lasts forever and there is no need to ever change your oil... for the sake of the oil. The problems are the additives and contaminants. The reason you change the oil is to replenish and renew the additives as well as evacuating contaminants. The only way to tell for certain is to do oil analysis to work your way up to the maximum usable life of the oil. He actually suggested in some instances one could be best served by doing a full oil/filter service and when the next service was due to change only the filter and replace only the amount of oil lost with the filter. That gives a shot of new additives and cleansers and new clean media to filter the oil. YMMV
 
He actually suggested in some instances one could be best served by doing a full oil/filter service and when the next service was due to change only the filter and replace only the amount of oil lost with the filter. That gives a shot of new additives and cleansers and new clean media to filter the oil. YMMV

Wonder what "some instances" he was talking about? Someone ought to do this experiment. Start with fresh oil and filter. At the first change, do as you suggest to replace the filter but remove enough oil to comply with oil testing companies requirements. Recent oil tests I did on new oil required 120cc (or thereabouts). Refill and continue to run the bike and see what the oil tests show. Probably would be best to first send in an used quantity of oil for a baseline. Then decide what to do at the second oil change...either just change the filter or maybe the oil depending on the results of the oil test. Or maybe drain the oil just before the second change and get it analyzed...then decide what to do.

It would be interesting to see what the "real" situation is. Of course, this would only apply to that one person and their bike! And yes, YMMV.
 
Sorry, I should have expanded on that. In "some instances" where there isn't much idling as well as not extended periods at very wide open throttle and no extreme loading. I guess basically if you mainly ride "sensibly" on the interstates you should be able to significantly extend intervals according to his personal engineering beliefs.
 
Wonder what "some instances" he was talking about? Someone ought to do this experiment. Start with fresh oil and filter. At the first change, do as you suggest to replace the filter but remove enough oil to comply with oil testing companies requirements. Recent oil tests I did on new oil required 120cc (or thereabouts). Refill and continue to run the bike and see what the oil tests show. Probably would be best to first send in an used quantity of oil for a baseline. Then decide what to do at the second oil change...either just change the filter or maybe the oil depending on the results of the oil test. Or maybe drain the oil just before the second change and get it analyzed...then decide what to do.

It would be interesting to see what the "real" situation is. Of course, this would only apply to that one person and their bike! And yes, YMMV.

FWIW - there are some interesting studies on this in the diesel world with special bypass filtration, etc. it's true that the oil itself doesn't really break down, it's the additive packages and filtration. (If I remember some of the studies there were over the road guys running 100k miles with regular filter changes and adding back additive packages.
 
I've got friends with OTR trucks and bypass systems with over 1/4 million miles without an oil change. That said, the bypass system has two different stations and when those filters are changed at filter change intervals I believe that's about 5-6 gallons of oil out of the total 15 or so gallons in the system every 25k or so. It's been several years since I looked into them and don't remember all the details now. They send in oil for analysis each time as well. It definitely saves a huge amount of oil compared to the not uncommon "change the oil every xK miles" that the oil/auto companies preached for so long.
 
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