Selkirk Engine Armor

[Chadx]

Not sure of that question was to me or "snowpromod" but no, I never considered a stock intake because i didn't want to cut extra vents and mess with frogzskin. Have messed with vents on other applications and wanted to avoid that again, but there is no way a stock intake, with plugged intake horns, can get enough air without adding venting. Would be really interesting to see the powerloss on a dyno. Maybe it's only a few hp.
Plus, on my previous two bikes (ktm based), I was used to running pods and open airboxes to get them to work right.

I've never had any snow around my YZ pod filter or piled on my engine much less enough to restrict it. Still not sure if that is a difference in my setup/covers/bib coverage to keep snow out, snow conditions, or what.

Needpower,
On days when you were getting that much snow on top of the engine that you were clogging a pod intake, what engine temps are you seeing? And what did you do to resolve that snow ingress?

[Edit: I started writing this, got distracted, then finished it but see needpower posted since then. I think it must be powder differences. I'm in southwest Montana so while powder os real powder and not coastal heavy, it is definitely not as llight as the utah pow! Ha. And my horns have 4" of foam so no air or snow getting through them. All air comes up from around engine.

 

[needpowder]

Chad X, yes that was for you about the “stock filter” setup
I thought that’s where you were located but I couldn’t quite remember. Doesn’t seem like our snow should be all that different? Some days, probably real similar. Engine temps compared to choking filter never really made a difference. On days that my filter clogged, obviously deep powder days with full engine jacket and radiators covered. Usually my temps were pretty good. Definitely cold on extended down hills 130-140. but not sure there’s really anything to do about that. Always warmed right back up going uphill.
If I am losing horsepower by clogging it is nothing I can feel. When my old set up would clog I would completely lose power and the result would often be a stuck.
Talking to Jeff at PR2, he said the pod on the Dyno versus the stock filter actually lost a little bit of horsepower. Obviously that’s not taking into account snow/air restriction. His explanation was that the stock Plenum was designed and tested on a Dyno by Yamaha engineers and with the pod you are getting rid of the plenum. (I think that’s what the rubber boot under the filter is called)
Obviously if your system is working then there is no reason to change it. Currently happy with mine as well!

 

[Chadx]

Chad X, yes that was for you about the “stock filter” setup
I thought that’s where you were located but I couldn’t quite remember. Doesn’t seem like our snow should be all that different? Some days, probably real similar. Engine temps compared to choking filter never really made a difference. On days that my filter clogged, obviously deep powder days with full engine jacket and radiators covered. Usually my temps were pretty good. Definitely cold on extended down hills 130-140. but not sure there’s really anything to do about that. Always warmed right back up going uphill.
If I am losing horsepower by clogging it is nothing I can feel. When my old set up would clog I would completely lose power and the result would often be a stuck.
Talking to Jeff at PR2, he said the pod on the Dyno versus the stock filter actually lost a little bit of horsepower. Obviously that’s not taking into account snow/air restriction. His explanation was that the stock Plenum was designed and tested on a Dyno by Yamaha engineers and with the pod you are getting rid of the plenum. (I think that’s what the rubber boot under the filter is called)
Obviously if your system is working then there is no reason to change it. Currently happy with mine as well!

Good info on your experience. Thanks!

Regarding the pr2 dyno, I do agree that a pod could lose a bit over stock, but id Jeff test with the horns totally plugged with foam which would greatly restrict the intake unless other venting was added? Everyone seems to plug the horns with foam so snow isn't shoveled in so if Jeff didn't plug the horns for his test, it would skew the results. And if he did, what additional venting, if any, did he add back in? Would be interesting to see the details.

It is a true science how those engineers design intakes and exhausts and how small changes can have weird results.

 

[needpowder]

Right. I’m sure he wasn’t plugging the horns! The foam I am using in the horns is fairly open so I am getting a bit of air there. Probably a little bit of snow dust also. Maybe not it’s so hard to tell where it’s coming from!

 

[snowpromod]

I’m definitely a rookie at all of this, but have tried to put together the best setup possible - that is the reason I invested in the Selkirk setup. My most recent riding was in Quebec with temperatures ranging from -16* to 26* Fahrenheit, we found excellent in your face powder.

I have my horns plugged with foam that is wrapped in outerwear prefilter material. I definitely need to figure out my snow ingestion problem because as of now the Selkirk is only acting as a big snow trap. It gets only warm enough to turn it into ice and collect even more snow - this not only affected the engine temp and air filter, but there was so much build up it would also affect the shifter. Last year I ran a PST engine jacket and CR intake and never experienced any of these issues.

I’m going back to drawing board to hopefully figure this out! These pictures are from this afternoon, I last rode the bike on Sunday and a bunch of snow has melted off already.

Sent from my iPhone using Tapatalk

 

[CATSLEDMAN1]

Comment about going down hill and temps dropping, when you run a true in the tunnel heat exchanger and have a well covered engine, dropping down a long deep powder slope temps go up to 200-210 because of low engine operating speed and slow coolant circulation, then back to 184 when you pickup throttle and engine speed increases.

 

[needpowder]

Comment about going down hill and temps dropping, when you run a true in the tunnel heat exchanger and have a well covered engine, dropping down a long deep powder slope temps go up to 200-210 because of low engine operating speed and slow coolant circulation, then back to 184 when you pickup throttle and engine speed increases.

Cat, I hear you. There have been times where I have covered every little piece of the engine and kept operating temps better. I just don’t find it as necessary because I am always yanking it out when conditions change, change my oil all the time, and am not worried about the temperatures i am seeing. I Have a tunnel cooler and all the plumbing from my old CR 500 sitting on the shelf and probably should have installed it at the beginning of the season but I was being lazy. And by the way, I am usually on the throttle going downhill in deep powder!

 

[harang90]

mossyz,
Your plumbing idea, of having two bypass circuits coming directly off the C3 thermostat, will work just fine. As you suggest, it doesn't matter where the valves are in each circuit (beginning, end, middle) it will reduce or cut flow in that circuit so the flow will increase in other circuits.

As I mentioned in a previous post, but I didn't elaborate much, another option is to plumb the selkirk heat exchanger on your open-thermostat, radiator circuit rather than on the bypass circuit. While this is not the selkirk-recommended installation, it seems logical to at least experiment with it. In the end, it made more sense to me and seems to work better for me on my 2020 YZ450F. When I was trying to get engine temps higher, I saw little reason to have the Selkirk heat exchanger on my bypass circuit and pulling heat out of the engine when I was trying to get engine temps higher. I only wanted active heat exchange when my engine needed to be cooled, so when my engine's thermostat opened. Since the C3 thermostat has an internal bypass, you'll always be pushing some coolant through your radiators (and heat exchanger the way I plumbed it) so no risk of cold shocking your engine. When my bike is warming up at the trailhead, well before the thermostat opens, if you put your hand on the radiators or selkirk head exchanger, they are warm since that small amount of coolant is always flowing through them. Once the thermostat opens, then a lot more runs through that circuit and cools the engine right down and thermostat closes again.

I keep my radiators uncovered on trail and covered when off trail. If there isn't a lot of powder, then I often leave radiators uncovered off trail, too. Temps off trail have mostly been staying 175 - 185 degrees F (I have a 194 degree F thermostat). Some super light powder days I might be down to 165 F. Way better than the 140 degrees it was running with the Selkirk plumbed on the bypass circuit. Plus, my engine doesn't cool off as fast when I stop for 5 minutes to talk and then start it back up. Was dropping to 120 degrees super fast (during a 5 minute stop) before I replumbed because heat exchanger sits in the deep snow cooling off and, when plumbed on the bypass, all that goes into the engine as soon as you start up. Some Yamaha owners have put spacers between the heat exchanger and lower surround so it cools off the engine less. I want the heat exchanger to remove as much heat as possible, but only when heat removal is needed, hence why I plumbed it on the radiator circuit. I love it plumbed this way and it works better for my particular bike and setup.

On the Yamahas, the radiators are plumbed in parallel and not series. The easiest place to add the heat exchanger to the circuit was in the lower radiator hose coming out of the right radiator. I was leaning towards it being on it's own circuit and receiving coolant before the radiators, but that complicated plumbing and valves/splits and, at that point, it was going to be a temporary experiment and first hand fact finding, but now I'm leaving it.

So my flow is as follows: A single bypass circuit out of the C3 thermostat goes only to C3 heated bars then back into the C3-provided lower radiator collector hose. My thermostat-on circuit flows to the top of the right radiator (like stock). Left Radiator plumbing is stock. For right radiator, the outbound hose coming out of the bottom, I put an inline adapter to reduce to the selkirk hose size, then it runs to the heat exchanger, comes back through another inline hose size addapter, then to stock hose size and into the stock metal Y collector. I originally did this just to experiment, but it works so wall, I'm leaving it.

Many ways to plumb these and have them work well. This was just the way that worked best for my bike, snow conditions, etc.



View attachment 339279

Chadx, just curious if you are still happy with the attached diagram of your plumbing for your handlebars on your YZ. I am in the process with the same system and like your theory, but wanted to 2X check prior to deviating from the Selkirk plumbing instructions.

 

[Chadx]

Chadx, just curious if you are still happy with the attached diagram of your plumbing for your handlebars on your YZ. I am in the process with the same system and like your theory, but wanted to 2X check prior to deviating from the Selkirk plumbing instructions.

@harang90
After running it for 3 winters, I still feel the most appropriate place for the selkirk heat exchanger is on the thermostat-open circuit rather than the bypass if your intent is to keep the engine temps up and leverage the selkirk heat exchanger for cooling once your thermostat opens.
That being said, I installed a C3 tunnel cooler on my Yeti 129 a couple weeks ago and did a radiator delete as well as removed the selkirk heat exchanger and associated plumbing. I am, of course, keeping the excellent selkirk engine surround as it is the backbone of my engine insulation solution. I've heat cycled and leak tested my new setup and will now secure hoses and button everything back up.

I'll be doing a thread on that entire update but I also shared a couple images on the XRT heat exchanger and coolant bottle thread since I used an XRT coolant bottle.

 

[harang90]

@harang90
After running it for 3 winters, I still feel the most appropriate place for the selkirk heat exchanger is on the thermostat-open circuit rather than the bypass if your intent is to keep the engine temps up and leverage the selkirk heat exchanger for cooling once your thermostat opens.
That being said, I installed a C3 tunnel cooler on my Yeti 129 a couple weeks ago and did a radiator delete as well as removed the selkirk heat exchanger and associated plumbing. I am, of course, keeping the excellent selkirk engine surround as it is the backbone of my engine insulation solution. I've heat cycled and leak tested my new setup and will now secure hoses and button everything back up.

I'll be doing a thread on that entire update but I also shared a couple images on the XRT heat exchanger and coolant bottle thread since I used an XRT coolant bottle.

Very nice, thanks for the reply and have a great season!!

 

[Chadx]

I’m definitely a rookie at all of this, but have tried to put together the best setup possible - that is the reason I invested in the Selkirk setup. My most recent riding was in Quebec with temperatures ranging from -16* to 26* Fahrenheit, we found excellent in your face powder.

I have my horns plugged with foam that is wrapped in outerwear prefilter material. I definitely need to figure out my snow ingestion problem because as of now the Selkirk is only acting as a big snow trap. It gets only warm enough to turn it into ice and collect even more snow - this not only affected the engine temp and air filter, but there was so much build up it would also affect the shifter. Last year I ran a PST engine jacket and CR intake and never experienced any of these issues.

I’m going back to drawing board to hopefully figure this out! These pictures are from this afternoon, I last rode the bike on Sunday and a bunch of snow has melted off already.

//uploads.tapatalk-cdn.com/20200211/571b3ee17ae10778c725c6d6e493bd75.jpg//uploads.tapatalk-cdn.com/20200211/633c9b6f4a36516a2e4adc74a11437c6.jpg//uploads.tapatalk-cdn.com/20200211/7cf392ce3404131cf802a67de9fddec6.jpg//uploads.tapatalk-cdn.com/20200211/392d53b295e34bdbce5e37b2dd5991b6.jpg

//uploads.tapatalk-cdn.com/20200211/4e6c0b628b23643f03eeeb632bfefc0f.jpg

@snowpromod
I'd missed your previous post from Feb 2020 and the images of a snow-packed selkirk engine surround. Did you figure out the cause of you snow ingress? I assume you were running the selkirk side panels and had just removed those for the pictures. How about the selkirm removable radiator blocker? I know it only blocks about 1/3 to 1/2 of the radiators, but curious if you were running that? (or maybe one of those isn't included anymore). I use that piece to hold in my full radiator bibs anytime I'm off trail in powder. If you look further back in this thread, you'll see some images. I've never had any snow inside my selkirk surround, even in handlebar deep snow days in blower powder and many stucks like you showed in your pictures. So curious if you resolved.