Change 45 flathead to overhead valve engine
 

I have a 1942 flathead (WLA). I am thinking of changing to an overhead valve engine, possibly with an electric start. I would like to keep the side shift and suicide clutch. Anyone know if this type of switch is reasonable to do? Any ideas what engines might fit this frame?

Your WLA looks beautiful, why do you want to ruin it?
If you seriously want a change, just buy a Sportster or some
Japaneese sportsbike and have instant OHV, just install hand shifter.
Probably you can fit some other engine into your wla frame,but what's the reason?

We have had the bike since 1962. I thought that it was a collection item, but from feedback I have received, it appears to be a civilianized WLA and not worth much. I am not a show person and just want to ride. The flathead leaks oil to oil the chain and seems to run a little hot sometimes, depending oh how much I have to advance the spark for power (seems to dechrome the header pipes with blueish tint). Since my objective is to ride lightly and the bike is worth little, I thought I would retain some of the neat qualities, but make it more ridedable.

Thanks

OHV and side valve are two different breeds. No conversion from one to the other.

Up until 1965 all HD ran on a constant loss system (oil diverted from motor over to the primary chain and dripped on the ground) and where I imagine the term was coined that Harleys mark their spot.

And you are aware that the spark should always be fully advanced when under power? You might need to retard it for starting purposes, but after that it is ALWAYS fully advanced. If you have to retard it to keep it running you have some timing issues you need to deal with and maybe some carb issues as well.

You just want to ride? Hell, that flattie is like a billy goat and while not fast it will eat up any roadway you put under it. They are easy and cheap to maintain as well.

Looked at some of your first posts. Did you ever figure out the title/vin issue?

To me your bike looks like civilian version, 16 inch rims, trim,etc. It's not military for sure.
Just put it on e-bay, you should get 7-8 G,and then buy some more modern dyna, sportster
or something newer. I'm sure there are guys looking to buy bike like yours.

agree, sell it then buy something newer. but not a sporty. id stick with riding it before id ride another sporty. if you could get $8000.00 there will be a lot of the bigger bikes you could pick up.

Thanks to all for the great information. I never got the vin# issue resolved. The title says it is a WLA, but the current motor does not match the title. We bought it in 1962 and it did not match then and we have not done any engine switches. I agree that it looks like a civilian, but am guessing it started out a WLA and went through a complete conversion. Someone pointed out that the front fender is not a match for the civilian model, indicating a remake.

I have decided to keep and ride the old 42, as I enjoy it and do not ride all that much (weekend pleasure trips). Now I just need to make sure it is running as good as it can. The top speed for me on the highway is about 55-60. Is that about right for these old 45s?

Also, it backfires during decelerations. In talking to my dad and uncle, they seem to think this is normal for these old 45s and can not be eliminated through tune ups. Does that sound right?

One more thing. Looking at the distributer head from the top, turning clockwise advances timing, right?

Thanks again

I was about 16 years old when I bought my "45". I can tell you it is one tough motor. I abused mine something awful, and it never let me down. I ran 90 wt. gear lube in the motor instead of more expensive Harley oil. Wish I still had it. I sold it in 56 for $50.00.

The top speed for me on the highway is about 55-60. Is that about right for these old 45s? Yes

Also, it backfires during decelerations. Might be timing but I would suspect it is a manifold leak.

Looking at the distributer head from the top, turning clockwise advances timing, right? NO. Moving the timer clockwise retards the timing; counterclockwise, all the way against the stop, places the timing in the full advance position. Retarding the timer can be used for easier starting, but once she fires up make sure you advance it completely.

Got it. Not riding too much yet in central Missouri, but will make sure I've got the advancing right when I get going this Spring. Thanks much.