Powder Coating Motors

Posted: Mon Jul 03, 2017 6:51 pm

Last year when my 1100F resto-mod was underway, I decided to powder coat my engine while it was apart for rebuilding. It came out really nice, and so far, after 1500 miles of fairly hard riding, the finish is holding up nicely. I can't keep it clean, though, since I ride it all the time. Sad

Since then I've powder coated two more engines with even better results. See below for the one I just finished this past weekend.

Now that I've got the technique mastered, I've decided to add this to my menu of powder coated parts. The head, cylinders, and case halves are all done separately and are carefully masked to keep powder off of any areas that it doesn't belong. The only thing I can't do is blast these - it's too risky to use aluminum oxide or any aggressive media on the case halves with the chance of some grit being left behind. Nils is going to collaborate with me and offer his vapor blasting service. Having him prepare the various engine parts will ensure that all crud and paint is removed before I start.

My service includes triple washing all the parts, outgassing in the oven, masking, and powder coating in the beautiful satin black you see down below. It's cured at 400 degrees and will be tougher than any paint used for the same job.

If you're interested, feel free to PM me to discuss the details. Nils can chime in here as well to include any details that he'd like to share. In the meantime, we've all see his beautiful work, so it speaks for itself.

Posted: Mon Jul 03, 2017 7:15 pm

Nice, better than new. beerchug

Chico

Posted: Mon Jul 03, 2017 7:25 pm

I'm not so sure, I believe most powder coat is a thermal barrier, unless it been specially formulated specifically to be a thermal dispersant. It might require careful thickness deployment as well.

PC does really look good though, and Tom, you certainly do a great job of powder coating, some of the best I've seen.

I did my cylinders in PC, then after reconsidering and thinking it looked like a blanket on them, I removed it and went with ceramic thermal dispersant instead, which goes on wet and thin, then is oven cured.

I got the advice about it from a guy that does ceramic finishes and metal polishing on Formula 1 and Gran Prix cars, among other clientele in hot rods and motorcycles to aviation. Sure, he's in business, so there may be bias, but what he said made sense at the time. I also looked around the net for anything I could read at the time that seemed to verify his position.

I also remember some mentions regarding electronics heat sinks that said not to PC them, as they would lose efficiency. Aluminum heat sinks are generally naked or anodized.

Getting that PC off was a real bitch. It took me many coatings of an Eastwood product that soaked for days each time, and finally media blasting to get it all off. BTW, I chose to leave the PC on my cases, it was just too much work to remove it.

I know I'd be interested if anyone has any real empirical data (or opinions) on PC thermal properties VS naked aluminum VS thermal dispersant nowadays.

Posted: Tue Jul 04, 2017 1:00 am

Should last very well, we started powder coating a few years ago, last winter we had an oven built that will allow us to bake an entire frame (even hard tail jobs that have been stretched). I will caution (as it inevitably come up) "chrome" powder coat looks like polished aluminium.

If you're on Facebook you can check out some of the jobs we've done: https://www.facebook.com/PanikSwitchCycle/

Looks great!

Posted: Tue Jul 04, 2017 1:57 am

Tom,
It looks like you've got it all scienced out, especially with the quality of work that Nils will provide. Sounds like a perfect partnership.

That motor looks great!

HD has been doing their motors for years and you gotta believe that if PC held in the heat, they couldn't cool the rear cylinder.

I've done a few PC motors and it's not easy with all the masking but, you can't spray liquid paint like you can apply powder into those hidden areas and deep between the fins.

I'd recommend the process for anyone that's looking for the best results.

Here's the last one I did:

Posted: Tue Jul 04, 2017 2:11 am

I like that look and have seen JRs CBX up close. Im interested in what Gene is saying and also looking to get my 1100 block done.

Posted: Tue Jul 04, 2017 1:10 pm

It looks awesome, to nice for Toddk Rolling Eyes

Toddk

Posted: Tue Jul 04, 2017 2:12 pm

If this leads to a double post sorry .. I was called away and it timed out so anyway...

I have considered the thermal transfer properties of our engines as well and the various types of refinish coatings available. On the 2017 spring ride TomK and I traded off on one of the afternoon segments and the ambient was hot by northern NY standards (he rode my 1985 VF1000R and I rode his F4i conversion bike with the powder coated motor) after we rode through Cooperstown in mostly stop and go traffic his powder coated 1100F motor was well within my acceptable range (I used my calibrated temperature testing method of placing gloved hand on the cylinder/head to see how hot the motor is getting.) Since I have built more than a few F-ing motors I was very interested in this tidbit of information!

At this point some of you may be thinking who gives a crap about Doc and his "gloved hand" but consider this .. I bought my Blue 1100F new and I have ridden it in every possible condition including riding into Needles CA at 114 degrees, around L.A. in heavy traffic, besides downtown Boston and to the Tail of the Dragon and back to NY so I know what hot feels like.

Back to our current story after our little stroll down memory lane ... Tom and I changed back to own bikes and my 100% stock VF1000R was really hot .. the cooling fans were running and the temp gauge was above 3/4 (I actually am considering discreetly installing a switch to turn the fans on earlier) and Tom's powder coated motor was just fine!

It would be nice to see some actual test data regarding cylinder, engine case, oil and exhaust pipe temperature on a side-by-side comparision.

Posted: Tue Jul 04, 2017 2:27 pm

DrOlds wrote:

If this leads to a double post sorry .. I was called away and it timed out so anyway...

I have considered the thermal transfer properties of our engines as well and the various types of refinish coatings available. On the 2017 spring ride TomK and I traded off on one of the afternoon segments and the ambient was hot by northern NY standards (he rode my 1985 VF1000R and I rode his F4i conversion bike with the powder coated motor) after we rode through Cooperstown in mostly stop and go traffic his powder coated 1100F motor was well within my acceptable range (I used my calibrated temperature testing method of placing gloved hand on the cylinder/head to see how hot the motor is getting.) Since I have built more than a few F-ing motors I was very interested in this tidbit of information!

At this point some of you may be thinking who gives a crap about Doc and his "gloved hand" but consider this .. I bought my Blue 1100F new and I have ridden it in every possible condition including riding into Needles CA at 114 degrees, around L.A. in heavy traffic, besides downtown Boston and to the Tail of the Dragon and back to NY so I know what hot feels like.

Back to our current story after our little stroll down memory lane ... Tom and I changed back to own bikes and my 100% stock VF1000R was really hot .. the cooling fans were running and the temp gauge was above 3/4 (I actually am considering discreetly installing a switch to turn the fans on earlier) and Tom's powder coated motor was just fine!

It would be nice to see some actual test data regarding cylinder, engine case, oil and exhaust pipe temperature on a side-by-side comparision.

Thanks Doc. Your calibrated glove is pretty accurate, so I think that settles it. Twisted Evil

Seriously, I will go for a good, hard ride with my son in the near future armed with a stock 1100F, (painted engine) resto-mod 1100F, (PC'd engine) IR heat gun, and clipboard with spreadsheet. I intend to take numerous A-B temperature readings on various points on the engines and at various points in the ride, including stops with the bikes idling after reaching full temp. I also want to take readings to see if there's a big difference in how fast they cool down once turned off. It won't surprise me to see a slight difference between the two, but based on the 1500 miles of riding already done with the PC'd motor, I don't expect any big surprises. I would have noticed thermal issues during the spring NE ride for sure if the motor got too hot in between 100 mile blasts at fairly high rates of speed.

Posted: Tue Jul 04, 2017 6:10 pm

My guess, after doing some more reading, is that you may not see a huge difference on a stockish street motor ridden on public streets.

But I don't think it's the way to go for a race motor, where one goes to great lengths to actually improve the cooling, and any step to lessen it would be taboo.

Posted: Tue Jul 04, 2017 7:19 pm

If it's a race motor, I'd leave it raw aluminum, period.

No point spending time and money to make it pretty if you just might blow it up on the next run.

Only exception, when you have a driver like ours that has a fetish for polished aluminum and stainless.............

Posted: Tue Jul 04, 2017 11:32 pm

Ha, well there's cases to say that polishing aluminum will make it less capable of shedding heat too, so there you go. Tends to close the pores I suppose. There are special thermal dispersant coatings and some newer nano tech stuff coming that is supposed to be much more effective at shedding heat.

Posted: Wed Jul 05, 2017 12:09 am

I think oil temp would be the way to compare pc vs non-pc engine temp differences. If the pc is keeping the heat in the aluminum, the surface temp of the powder coat may not tell the whole story. The less efficiently the fins work to cool the engine the hotter the oil temp should be.

As usual Tom your works looks top notch!

Cheers
Nich

Posted: Wed Jul 05, 2017 12:30 am

BTW, the inlet tube gets an instant cover of frost even on the hottest days at Bonneville. People just can't figure that out. LOL.

Posted: Wed Jul 05, 2017 12:45 am

CBX-tras wrote:

BTW, the inlet tube gets an instant cover of frost even on the hottest days at Bonneville. People just can't figure that out. LOL.

I've heard of that before. Has to do with the pressure drop?

Posted: Wed Jul 05, 2017 1:25 am

Are you guys (Tom, JR) leaving the sides of the five fins bare like the original 1100F or are you painting them silver for the same effect? The motors look great!

Posted: Wed Jul 05, 2017 3:44 am

The coating was removed on the edges of the fins on this one with a large floor standing belt sander after the finish was done. One swipe per side, he obviously had used it a lot. He's the guy that does the F1 and GP cars I mentioned before.

Posted: Wed Jul 05, 2017 11:14 am

hogwild113 wrote:

Are you guys (Tom, JR) leaving the sides of the five fins bare like the original 1100F or are you painting them silver for the same effect? The motors look great!

I sand/shine up the edges of the fins prior to PC. After I shoot the part, I wipe off the powder from the edges BEFORE the head goes in the oven. After curing, I give them a quick touch-up with emery paper and they look stock as desired. Removing cured powder from the edges after curing would be a nightmare.

Posted: Wed Jul 05, 2017 2:19 pm

genesound wrote:

CBX-tras wrote:

BTW, the inlet tube gets an instant cover of frost even on the hottest days at Bonneville. People just can't figure that out. LOL.

I've heard of that before. Has to do with the pressure drop?

Evaporative cooling of the 100% methanol. Same thing that makes A/C work.