Harley-Powered?

[rv6ejguy]

Originally Posted by rv7boy

Let's all take a deep breath, exhale and think before we post. I don't see any objectionable posts in this thread yet, but I must remind you this is an RV forum, not a motorcycle forum. I like to ride cycles, too, but let's not get into a "which motorcycle is better" discussion. I see the potential for this thread to veer off the RV path. Nuf said?
If in doubt... read the rules. Doug has the link in the middle of the first page of the forums.
Thanks and keep on posting...about RV stuff.
Don

I think this came from another post on RV12 alternative engines. http://www.hog-air.com/hogindex.htm

This company is providing Harley aero engine conversions for other LSA type airframes at the moment and it may be applicable to the RV12. I am always interested in others experiences with powerplants- especially from a reliability standpoint. Yes, threads drift a bit but the other motorcycle thread is far less RV related in my view.

[xl1200r]

HD engines aren't really inefficient by design in order to get "that sound". While in some applications, the 45* common crankpin v-twin is less than optimal, there are advantages to be found. For instance, a common crank v-twin in a 45* config will make more tourque than one of the same internal dimensions in a 60* or 90* configuration.

As for the reliability, there have been quite a few trouble free miles on modern HD twins. Now, AMF days are not included with this obviously, and anything before 1968 can hardley be called reliable. Not to say that other engines aren't equally (dare I say more? Nope.....) reliable, I wouldn't think twice about putting one in an airplane provided proof that the engine would tolerate that kind of use (abuse), as I would with any non-aircraft engine.

Actaully, come to think of it - I wonder how the Honda flat-6 that's used in the Goldwings and Valkyries might far for RV duty???

[RVbySDI]

Originally Posted by xl1200r

Actaully, come to think of it - I wonder how the Honda flat-6 that's used in the Goldwings and Valkyries might far for RV duty???

I think these would work very well if the weight were not too much of a problem to overcome. I would be curious about what the weight is for those engines.

[xl1200r]

Originally Posted by RVbySDI

I think these would work very well if the weight were not too much of a problem to overcome. I would be curious about what the weight is for those engines.

I'm having a hard time finding weight figures. The best I can find is the 1800 is 1kg lighter than the 1500. There are some issues though - they are a six, which means less room for a redrive - is this a problem with the Egg H6 mills? They also only make 118hp. That leaves a lot to be desired for RV apps, though I'm not sure the how the aftermarket is for these engines either.

[RVbySDI]

Originally Posted by xl1200r

There are some issues though - they are a six, which means less room for a redrive - is this a problem with the Egg H6 mills?

The Subaru engine is a boxer instead of straight six so they are going to be more compact than these engines.

[Harvey]

While I realise that this is a little off-topic, there are some points regarding H-D power that I wish to make. Harley engines are not 'designed' to be inefficient - they are designed to chug along without using a lot of revs, just like any big ol' Lycoming.

Work out the hp per cubic inch - the Harley TC88 puts out around 40 hp per 44 ci cylinder, the Lyc O-320 puts out 40 hp per 40 ci cylinder. The Harley revs more to make the power though.
An interesting aspect of the H-D bottom end is the knife and fork con-rod set up, similar to the RR Merlin V-12, and allows the cylinders to be set inline with each other, rather than offset like the Lycoming. This reduces the 'rocking couple' - a cause of secondary vibration. The 45 degree layout ensures the mill vibrates regardless.

The bottom line is that the H-D engine will shake all your rivets loose anyway, though it could be mounted like in the Buell, but I just don't think the engine will take to running hard like it would have to in the aviation environment.

Martin

[xl1200r]

Originally Posted by RVbySDI

The Subaru engine is a boxer instead of straight six so they are going to be more compact than these engines.

The Goldwing is an H6 as well. I don't know of any Inline-6 engine in a bike - there's just no room for it.

[Red Voodoo]

"I don't know of any Inline-6 engine in a bike - there's just no room for it."

Depends on how you orient the mill. Gone but not forgotten:

http://www.motorcycle-usa.com/Articl...eID=822&Page=1

http://www.motorcyclespecs.co.za/mod...z1300%2084.htm

[Mike S]

Originally Posted by Harvey

the Lyc O-320 puts out 40 hp per 40 ci cylinder.
Martin

Nope.

Lyc is 80 cu/in per cly, typ H.P. is 37.5 or 40, depending on engine.

Mike

[xl1200r]

Originally Posted by Red Voodoo

"I don't know of any Inline-6 engine in a bike - there's just no room for it."

Depends on how you orient the mill. Gone but not forgotten:

http://www.motorcycle-usa.com/Articl...eID=822&Page=1

http://www.motorcyclespecs.co.za/mod...z1300%2084.htm

I stand corrected:


Though I think we can all admit that was about as much overkill as trying to get a Chevy 725hp 572cid crate strapped to the front of a -3