Flame Arrestor question?

[tomsl750]

Bryan, I bought my sl750 used. I was wondering if I had an aftermarket (Polaris Branded) flame arrestor. It doesn't look like the one in my manual. The one on the ski had a blue metal top that says polaris on it and then the filter all the way around. It is sort of a dark reddish tint (Like the K&N)and then the bottom is blue with all the plumbing (For the oil injectors). My question to you, or any one else that can help (Sealion?) is...Is this an aftermarket f/a? Also, would you recommend the Boyesen power reeds or the pro reeds for general recreational use as far as longevity of the reeds and durability for the engine. Thanks.

[Bryan Glynn]

Sounds like a stock filter to me - they had several designs.

For the reeds, I can tell you I put 80 hours on my last set of Pro reeds, that performed very well, and they still look new. A key to reed longevity is a spacer plate.

[tomsl750]

Where is the best place to get the reeds? How hard are they to replace them? Should I attempt this or let a "professional" do the work. I am fairly handy with tools, but I don't want to mess up my baby.

[Bryan Glynn]

Replacing them is easy - you can get instructions in our Technical section - download the Install guide and follow the appropriate steps. I'm not sure what the best place to get them would be besides your dealer.

[tomsl750]

If I do get the reeds, I will have to get new gaskets as well, right? Also, to get to the low and high speed screws, I will have to remove the f/a, right? As it seems right now, the only adjustment screw I can actually get to is the idle speed screw. If I remove the f/a, won't that mess with the oil injection? Please help me on this one.

[Bryan Glynn]

Yes you will need new gaskets, and no, taking the FA off will not 'mess up' the injection - the base will just lift off.

[SeaLion]

You do have a Polaris aftermarket type filter. It is an R&D open element plenum style. I have to disagree with Bryan about the SL750 coming with different types stock. They did not. The stock one is blue plastic and has a slight radius to the top. There is no open element. As far as the reeds, the Pro series are fine but definitely won't last as long as the fiberglass ones. Whichever reeds you go with, it is mandatory IMO to add the 3/8" reed cage spacers at the same time.

[Bryan Glynn]

You're right, that the 750's all came with the closed plastic type - but there are several Polaris designs that fit, such as the Ocean Pro type off the 780's, that are popular to switch.

[SeaLion]

The OP are 3 individual pieces and they did come stock only on the SLX780 but not any other 780. It sounds like the guy has a plenum F/A though. Either way, it is not stock and is better than the stock set up. The bonus is that he still retained the oil injection. I am curious where the fuel pump is mounted because getting rid od the stock set up forces you to mount the fuel pump somewhere else.

[tomsl750]

Sealion, the fuel pump is located on the hull with a metal fabricated bracket about 1/2 way up almost directly beneath the f/a. You think that it is an R&D 'polaris' aftermarket? I am turning about 6200 at about 48mph on the water. Is this good? What kind of performance gains can I get from new reeds. Will the f/a need to be removed for me to adjust the carbs after the new reeds have been put in? What is the best type of reed (brand and model) would you recommend for recreational riding. Any input would be nice. Also, what do you think of the ride plate at purepolaris.com? I have been told that it is just an R&D intake. It sure is a hell of alot cheaper than the R&D branded one. Also, I know that you have recommended the rideplate, but I forget what brand. I think you said OP, but I couldn't remember. Where can I find one? Also what mods have you made to your polaris that would be good for me? Thanks guys for listening to me ramble.

[tomsl750]

Sorry, the ride plate should have read intake grate at purepolaris.com

[SeaLion]

The intake grate is an R&D for $29.99 from Polaris. Little known secret money saver [img]smile.gif[/img] I personally wouldn't put one on an SL750 because you will lose 2 mph. If you ride in lots of chop then maybe try it for the $29.99 price and you can always sell it for that much on ebay if you don't like it. Your rpm figure is right on for the SL750. The boyesen reeds are good and there is a set of the Pro Series on ebay right now for a good price. the link is: http://cgi.ebay.com/aw-cgi/eBayISAPI...tem=1147278160 .

Like I said before, you should put the 3/8" reed cage spacers on at the same time as doing the reeds. http://www.choppercity.com has them as does http://www.boyesen.com/products/wate...vespacers.html . The Boyesen link has downloadable detailed instructions and are anodized where the chopper city ones are just aluminum. The spacers will enable the reeds to last much much longer while boosting mid range as well.
If you are interested, I have a set of Boyesen fiberglass reeds mounted on Pro785 cages with stuffers that have 1 hour on them? I found a set of Boyesen RAD Valves right after I installed the fiberglass reeds so that is why there is only 1 hour of use on them. I also have a set of the factory Polaris reed cage spacers with the longer studs that are take offs from my SLX.

I also have a set of OP Vortex F/A's, but you already have a good F/A on there.

For the rideplate, Ocean Pro is the ONLY plate that I could recommend. It should be the first mod to any Polaris 2 seater hull. Call Ken at OP and tell him I referred you. He will set you up. His number is 1-800-553-6650.

I also had good luck with a 92 octane pump gas head mod. A 4" pump extension yields a solid 2mph but is fairly costly to justify the $400 price tag. If you can find a used one for much less than go for it? The stock 5 blade impeller is not the greatest and a Skat Swirl in a 13/18 or12/17 pitch is great for hook up and bottom end while not scrubbing any top speed. You can modify your stock intake grate by cutting the 2 middle bars out of it but depending on how much debris is in the water you ride you might want to consider the possibility of sucking up more stuff.

I just remembered that I also have my stock SLX cdi with a different timing curve than the SL750 but this would be experimental on your part. I didn't have one on my SL750 but I can see it boosting bottom and mid range on an SL750. I am actually running a Pro785 CDI in my SLX.

One more secret [img]smile.gif[/img] is using a 92-93 SL650 pipe for major rpm boost (about 400), but that set up is difficult to dial in. I am using it on my SLX and it screams but it took me a long time to dial it in. With the SL750 having a different ex. manifold and less agressive porting than a stock SLX, I would not be able to help because I have no experience with it. I actually bought the used 92-93 SL650 pipe for my SL750 but I sold it to get the SLX before putting it on and setting it up.

Enough of my rambling, LOL. Let me know if you have any more questions.

[tomsl750]

The reeds are the pr029, the one's I was looking at was the milder pr028. Boyesen recommends the 29's for racing, while the 28's are for recreation. I am just looking for a more recreational ride for me and my girlfriend. I am considering the ride plate and the reeds to start. I shouldn't go to the intake grate because their is a lot of debris in the form of weeds that float around the lake I'm at. It is nice to know about the f/a though. Now I can shell out some $ for the reeds and the rideplate, as soon as I actually get some extra cash. What do you think about a new waterbox. I have seen the TRD waterboxes for about 150. Are they worth the money IYO. I am trying to set up a nice ski on a college budget. How much for the rideplate (approx.) I will get that before the reeds, probably. Thanks for your previous and future input on my little extracurricular college project. Georgia Southwestern Biology major 3.57GPA.

[SeaLion]

The rideplate retails for around $100 but Ken will sell it cheaper. Call him and tell him I sent you. He'll hook you up. Make sure to put the reed cage spacers on when you do the reeds. The TDR waterbox is louder than stock and yields a little more bottom end but you won't notice any top end gains. I have one of those as well if you're interested? $75 shipped sound good? It is bulky so shipping alone would be around $15.
A 4* pump wedge will give you a little more top end by lifting the bow out of the water more.

[tomsl750]

Sealion, how much louder is the waterbox? I know it is hard to quantify sound, but will I be able to talk with another rider without shouting while cruising at about 4500rpm? I think I'll give that guy a buzz about the rideplate. It all depends on what the wife says, LOL.