Engine, transmission and primary oil change notes for M8

[IronButt70]

Just curious as to why you never use 6th gear?

A couple of reasons:

1 - The MPG is reasonable.
2 - The engine seems like it likes to be at or around 3K RPM. In 6th gear it feels very lethargic to me.
3 - I can coast through small towns at 45 MPH (2090 RPM) and cruise on the interstate at 70 MPH (3250 RPM) without having to shift.
4 - As the wind resistance gets higher as the bike goes faster, the engine power increases to match.
5 - Peak torque is at 3250 RPM so both 70 MPH (5th) and 80 MPH (6th, if I need to go that fast) are right there at the peak.

I don't think I am wearing the engine out prematurely. I posted a thread on this when I got my first HD: http://www.harleytechtalk.com/htt/index.php?topic=88299

On my last two HDs I used 6th a lot to see if I liked it and it didn't "do it" for me.

If I'm wrong doing what I am doing I am willing to change. I like to learn new stuff.

If it works for you that's all that matters. Here are my thoughts FWIW.
Running at higher RPMs is going to cause more wear in the long run. How much more or does it really matter is the wild card.
More RPMs mean more fuel which means more heat. How much more @70 mph is anyone's guess but there will be more to dissipate IMHO.
Mileage is not always the determining factor for engine wear. The amount of fuel put through the engine to get to x amount of miles also comes into play. You said your MPG was acceptable in 5th but it's not optimal.
All that said, if it works for you than its good. I never run below 60 mph in 6th and there are times when I will stay in 5th above that depending on conditions.
Be safe out there.

[lonegoosehonking]

"I run Formula+ in the transmission and primary just in case the oil migrates."


Xyzzy ,
           Did you notice any difference running the Formula + in the transmission vs. the Mobil gear oil?

[Xyzzy]

I noticed no difference.

I order my Mobil 1 stuff from Pep Boys on eBay, so it is delivered to my house free.

I have to go to the dealer to get the Formula+, which is a PITA.

PS - I traded in all of my bikes and bought a '17 Low Rider S, so I won't have any more data for this thread. Because it has a cable-actuated clutch I suppose I won't have to worry about transmission oil migration either.

[krwson]

PS - I traded in all of my bikes and bought a '17 Low Rider S, so I won't have any more data for this thread. Because it has a cable-actuated clutch I suppose I won't have to worry about transmission oil migration either.


Good idea on the trade in's, although as much as u ride your going to mis the ride of the baggers. Any up dates on the Low Rider ? 👍

[Will-Run]

For sure , lets hear up dates and thoughts on the S bike.

[Xyzzy]

Good idea on the trade in's, although as much as u ride your going to mis the ride of the baggers. Any up dates on the Low Rider ? 👍

The LRS is more comfortable and the suspension is more compliant. I kinda miss the bags on the "bigger" bikes but so far I am dealing with it fine. I put 5,000 miles on it in the first 16 days I had it, including 1,100 miles in 19 hours, so it fits me good and makes for a great long-ride bike. It has cruise control which is a must-have feature. I don't think it is more powerful than the M8 107 but it does have a lot more low end torque and it revs much faster. I'm still using 5th gear max even though it will pull sixth at 70 MPH. It is geared higher and I don't like how the engine feels at ~2,600 RPM at 70 MPH in sixth. In fifth at 70 MPH it is turning just a smidge over 3,000 RPM. I have added a Power Vision tuner and a V&H Hi-Output 2-1 short pipe.

[krwson]

  I like your plan.

[Xyzzy]

An update:

A few weeks ago (June 6th) I bought a M8 Softail Fat Bob.

I've done the 1K and 5K service already and I plan to do the 10K service maybe this weekend. (I have 9.3K on it as of today.)

A few months ago a pal convinced me to switch from Mobil 1 to Redline oil. So far I am pretty happy with the Redline stuff. I am using the 20W50 engine oil, "V-Twin" (MTL) primary oil and "V-Twin" (heavy shockproof) transmission oil.

I drain the engine oil out with the bike super hot and a lot comes out. I add 4.5 quarts back in and that puts the level in the lower third of the dip stick. I'm pretty sure as long as oil shows on the dipstick the engine is fine. Checking the oil is really easy because there is plenty of room to work in that area without getting burned by the pipe.

The primary is a bit weird because the manual has two different fill amounts depending on the primary size, but they don't tell you which size you have. I measured the factory fill in my primary and it was 42 ounces, so I guess I have a wide primary. I tried adding a few extra ounces but the shifting got real rough so I'm sticking with the 42 ounces.

The transmission is pretty simple. I just put the whole quart in. I was skeptical that the shockproof oil would make a difference but it actually made finding neutral much easier.

I don't expect to see any transfer from the transmission to the primary but I will check just to be sure. Since I have a cable clutch I think I will be good to go.

I'm not a Softail kind of guy. None of the TC Softails ever interested me. But the Fat Bob looks amazing and handles really well. Compared to my old LRS the FB handles significantly better, especially in how stable it is holding a line in a curve at high speed. The LRS engine felt like the powerband hit harder but without a doubt the FB has more torque down low. That said, the LRS sounded much better, but I had really loud pipes on it and my FB is stock. FWIW, I test rode the 107 and the 114 FB and didn't notice much of a difference in power output, so I "saved" $2K and got the 107.

As an experiment I am using the shift points in the manual, so I am spending a lot of time in 6th gear at 55 MPH at 2,000 RPM. Maybe because the weight and frontal area of the FB is much less than a SG or RK is the reason I can get away with this low RPM operation. From what I can remember, the Softail M8 transmissions are roughly 200 RPM lower at any point compared to a touring M8 transmission.

Either the bike will survive this treatment or it will catch on fire. It is under warranty so I'm not overly concerned. I think it will be an interesting test since I rode my previous bikes at a much higher RPM. My fuel economy so far has been very good and the relaxed cadence of the engine sounds nicer. I never would have been able to ride this low with my TC RG. The compensator on that bike made horrible thrashing sounds and "kicked back" when I turned the bike off. I can only assume the better compensator lubrication, lighter weight and increased low end torque makes this viable. I recently rode 22K miles on a Sportster 48 that had no compensator so if I did experience compensator issues with this FB I would be tempted to put a solid sprocket in.

Anyways, I hope this was helpful and/or interesting. If you have any questions or ideas you want tested just let me know!

[fxstd_01]

The primary is a bit weird because the manual has two different fill amounts depending on the primary size, but they don't tell you which size you have. I measured the factory fill in my primary and it was 42 ounces, so I guess I have a wide primary. I tried adding a few extra ounces but the shifting got real rough so I'm sticking with the 42 ounces.

As I understand it, if you have the 240 rear tire you've got the wide primary, the 180's have narrow.

Damn, you go through some motorsickles.  Great thread, thanks!

-jeff

[Will-Run]

With the miles you put on, I have to ask.When the f**k , do you sleep and eat?.

[Xyzzy]

With the miles you put on, I have to ask.When the f**k , do you sleep and eat?.

I don't watch TV or do Facebook, so that frees up a lot of time.

Yesterday was the half way point for the year. My goal is 100K miles this year. I got 72K last year. So far this year I am at 46K.

Maybe someday Harley will "hire" me by giving me a new bike every year to do an extended reliability/usability test. I have tons of feedback I could give them.

Just today I passed 10K on the Fat Bob. It took me 26 days. The weather has been really hot but I'd rather be hot than cold. I hate the cold!

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[Xyzzy]

As I understand it, if you have the 240 rear tire you've got the wide primary, the 180's have narrow.

You are right! I don't know why my factory fill was 42OZ. Weird!

From the parts fiche:

Fat Boy: 36500114 INNER PRIMARY HOUSING WITH 60328-98B (WIDE)(BLACK)
Fat Bob: 36500104 INNER PRIMARY HOUSING WITH 60328-98B (BLACK)

[Ohio HD]

With the miles you put on, I have to ask.When the f**k , do you sleep and eat?.

I don't watch TV or do Facebook, so that frees up a lot of time.

Yesterday was the half way point for the year. My goal is 100K miles this year. I got 72K last year. So far this year I am at 46K.

Maybe someday Harley will "hire" me by giving me a new bike every year to do an extended reliability/usability test. I have tons of feedback I could give them.

Just today I passed 10K on the Fat Bob. It took me 26 days. The weather has been really hot but I'd rather be hot than cold. I hate the cold!

[attach=1]

HD had an ad out about four months ago looking for test riders. They've hired people to do that for over 30 years. They used to put ads in the back of cycle magazines.

[Xyzzy]

15K miles took me 39 days.

I just changed the air filter. It had just a little oil on the bottom. The TB had maybe ¼ teaspoon of clean oil pooled in it. Nowhere close to as messy as my previous bikes.

I change air filters probably too often, but for $15 I think it is a good deal. I live in a real dusty area so maybe it qualifies as extreme service? Maybe I'm wasting my money but it helps me sleep better knowing the filter is clean.

[Xyzzy]

Stats:

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[Xyzzy]

Dunno if this is useful:

At 15K, 4.5/32" on the rear and 4/32" on the front.

I really don't like these tires. If they ever wear out I will replace them with something more "normal".

Even new they had a thumpy feel to them pushing the bike around on smooth concrete. It feels like pushing a dirt bike with knobby tires around.

I haven't dragged even the peg feelers yet so they have plenty of grip, but the tires feel "vague" to me. I took the bike to "The Snake" a few weeks ago and really pushed the bike hard. The front end (tire) will push a bit on corners and powering out of turns the rear (tire) has a greasy feel and will lose traction pretty easily

The chassis and suspension is superb. I had a LRS with $1500 Ohlins shocks that I thought handled good, but this bike is light-years better stock.

[Hossamania]

Those tires look great for having 15,000 miles on them.

[Xyzzy]

I managed to squeeze 20K from the tires.

It took me 53 days to do 20,000 miles.

My fuel log is here: http://www.mersenneforum.org/png/MPG.PNG

No problems to report! Everything works great!

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[Xyzzy]

It took me 80 days to do 25,000 miles.

My fuel log is here: http://www.mersenneforum.org/png/MPG.PNG

No problems to report! Everything works great!

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[Hossamania]

I am impressed and very jealous. Really glad you are enjoying your bike.

[Xyzzy]

A few days ago I was at my local dealer. They had a bunch of new 2019 bikes in. I suggested that they needed to discount the 2018 bikes to move them to make room, and that I'd be willing to trade my Fat Bob for a Softail Slim straight up. Suprisingly, they took me up on that offer so I went from a 2018 Fat Bob with 27,000 miles to a 2018 Softail Slim with 10 miles. No money changed hands. It was a straight swap. The Fat Bob retails for about $1,000 more than a Softail Slim. I think taking a $1,000 "hit" for 27,000 miles is a pretty good deal!

[Pete_Vit]

A few days ago I was at my local dealer. They had a bunch of new 2019 bikes in. I suggested that they needed to discount the 2018 bikes to move them to make room, and that I'd be willing to trade my Fat Bob for a Softail Slim straight up. Suprisingly, they took me up on that offer so I went from a 2018 Fat Bob with 27,000 miles to a 2018 Softail Slim with 10 miles. No money changed hands. It was a straight swap. The Fat Bob retails for about $1,000 more than a Softail Slim. I think taking a $1,000 "hit" for 27,000 miles is a pretty good deal!

wow ! not often do you see that.

[Hossamania]

I'd say you did well on that deal.

[Phu Cat]

I hate to be the bearer of bad news, Xyzzy, but ya can't tell a darned thing about oil by lookin at it.  The oil that's dark is possibly contaminated with engine oil, and the light color oil may have more contaminates in it than you're aware, like acid for example, which is clear.

Where's I get this info?  Straight from the lubrication engineers I worked with.

PC

[Xyzzy]

They didn't route the spark plug wire differently on the M8, so check your front left plug wire for chafing where it touches the fuel tank. Mine had a divot wore in it so I wrapped some electrical tape around that area.

I picked up a 2019 RK today.

HD finally fixed the spark plug wire issue!



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