485 Motor Or 540?

Yamahammer485

Yamahammer485

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Joined
Dec 19, 2005
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574
Age
37
Location
Espanola, Ontario, Canada
Hey everyone

I want a Yamaha fan cooled motor for my sled, and want the most powerful one I can get. This motor will be modded quite a bit by porting, shaving heads, cleaning up transfer ports, etc....

Im just trying to think what would be best in this case. I want to use a Phazer AAEN pipe with this modded motor so im not 100% if its compatible with the 540, and same with my reeds. Also, the 540 would be twin carbbed, and I heard that this is hard to do because tuning it is difficult. Iv heard that when modded, the phazer motor makes more power, but find this hard to beleive as it has smaller displacement.

Also, anyone know if the Yamaha YXR primary can fit on the crankshaft of the 540 motor? Or even if the 540 will mount directly into the phazer engine mounts, like on the frame?

Most importantly, which is the best motor to modify to make a really strong motor?
 
I assume your talking about the srv motor?I am not an authority on the subject by any means ,but it seems like the 540 had some issues.Most of the srv's I remember running around back in the day that were a few years old or more had either 440 ss motors or phazer engines in them because the owner could'nt keep the original engine together.Maybe some were ok, but I am not sure maybe someone else could chyme in on this, the phazer engines sure were tough though,that may be your best bet.
 
My brother has a -85 SR-V and it walks all over any phazer there is. Stock ofcourse.

The 540 (535cc) is a great fan cooled engine. The phazer 485 is good, but not in the same league. With a PSI single pipe and some mild porting the 540 makes almost 90 hp... + Yamaha offered ´85 (go to parts catalog at Yamaha Motor site and you´ll find it) alternative race parts to that engine too (dual carbs etc. ). Those parts are hard to find...

14llpgk.jpg


Big bore it to 551cc (1mm over stock ) and it will give 500cc LC sleds hard time. Been there done that.

http://media.putfile.com/SRV--8485-doing-14008-kmh
Here is my brother going 140,08 kmh with his stock SR-V last winter. It was radar run at Muhos.

http://www.vmax4.com/vbulletin/showthread.php?t=258

http://www.m-performance.com/Grafik/Dynobilder/yamaha/srvbempas.jpg

http://www.m-performance.com/Sidor/dyno_yamaha.htm



Ike
 
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Thanks guys

Ike, thats a good bit of info right there. I went and checked out the site, but didnt find any dual carbs info. Also, you have any idea what those race parts do that yamaha sells?, like possibly higher comp heads or something.

If I do anything, Ill have the 540 bored to 551, then shaved heads, porting, dual carbs. Any info on these mods or is there any other possible mods?

Good info guys, im going to be lookin around for a while before I make my descision however.
 
Race parts :

ported cylinders, different reeds, different heads atleast (part numbers are different than stock ones). More top end speed and more responsive trough the rpm range. My dealer said that that race part thing had dual carbs too, but seems like no more. Here in europe Yamaha offered that option. Seems like they only have that single carb there anymore. I´ll do more diggin for you. And I´ll talk my brother to answer here too. He knows those SR-Vs like his own pockets!

When big boring 540 engine remember, especially when cutting heads, run ONLY premium fuel. My bro´s SR-V is kind of picky with the fuel. Old tech you know. Build when the fuel had plenty of led in it.

Along with PSI, I know that Decker build pipes for SR-V too. Good ones I hear.
 
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Awsome!

Thanks so much man!!

Any Idea of a phazer pipe(99 or newer) will work with an Srv motor for engine RPM ad exhuast flow? Maybe even a 500/600 LC pipe. Reason I say this is because the SRV pipe will not fit my cab or mounting brakets, and is so off shape that you cant exactly just change a few angles. The SRV pipe is really square shaped.
 
I´m in no means a expert on those pipes, but I can and try to find out for you. Yes, the SR-V pipe is square as a pipe can be lol

We have one Decker single pipe at our garage where the sleds are. I´ll post a pic of it soon as possible for you. It´s over 100km´s away but soon as I go there I´ll take a pic of it.

I´ll talk to my friends who have done business with PSI, Jaws, Bender etc. with 2-stroke stuff. They should give me an answer.

Talk to you soon and I´m glad that I could give you info for your project.

Ike
 
Awsome stuff!

Im going to be lookin around for a used 540 engine in my area for the next while, just to see whats available.

You think itd be better to just go with the OEM Yamaha racing cylinders and stuff, because they are already modded (thats if they still sell them), or just a stock 540 motor and have it ported and heads shaved, and bored over to 551cc?
 
or you can use phazer intakes if they will work i your venture? if not find a set of RPC intakes......they were the only aftermarket company to offer dual intakes for the SRV...and AAEN was the only aftermarket company to offer twin pipes for the SRV.....these are both pretty hard to find...but they are out there....I wish I did not sell my rpc intakes!!!
 
RPC isnt still around are they?

Do you know what pipes I can use with the 540 motor? Im thinkin along the lines of a 500/600 LC yamaha sled pipes as they would fit my chassis, and are close to the displacement of the 551, and not sure, but do they have similar powerbands?
 
Yamahammer485...if you do drop in a 540 you have got to do twin pipes. If you are looking for custom twins i know a guy who makes them custom fit for your sled and they make some really amazing numbers. buuuut the pipes cost 2000 dollars Can. The reason for it being so expensive is because the guy tests and test over and over for best hp numbers. Guy is located in toronto. He isnt as interested in sleds anymore but when he was he made a 300hp drag rotary sled. now hes got 1400 hp turbo rotary rx7.

fined some 40 mm carbs to put on also......and paint the hood. it would look so nice after that


If anyone is interested in the pipes let me know i can link you to the web site.

i cant seem to remember it right know :o|
 
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Thanks Ike, I didnt get a chance to check their site up until now.

Dave Vmax600, does he still make the pipes for sleds although he isnt interested in them anymore? Maybe it would be better to find a set of twin pipes for a Vmax600 in the proaction chassis and make them work with the 540....
Dont know if this is possible though...

Thanks guys for everything so far!
 
Awsome, thank you!

My buddy has a SRV540, and its boed over the second most you can bore it over to, and im not sure what that is exactly, but apprently, Wiseco wan out of pistons for that particular bore for the year. Is this actually possible? Im not necessarily thinking of this motor, but was jsut curious as I want the motor bored over and will be using Wiseco pistons.
 
I talked to my brother. He actually has twin pipes for his SR-V + that Decker single pipe. We´ll post pic for you about them.

Wiseco has pistons for 551 big bore. And Yamaha has also 0,25mm and 0,50mm over stock pistons too...

14t0xty.jpg


Later,

Ike
 
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Im going to try to find an entire motor in my area first, so that I can get the whole thing modded, but if something ever goes wrong, ill keep you offer in mind. Thanks!

Thanks Ike, I must have missed that looking over yamahas parts catologue. Iv heard alot of people prefer the stock pistons over the Wisecos, and might keep that in mind.

Im still on the descision of the 485 vs the 535. Because im hearing the the 535 doesnt make top end like the phazer, and it runs better with single carb, and I dont want no friggen single carb like my 250 elan twin. AND, I will ahve to custom fab some mounts to get the motor to fit and keeping everything aligned might be hard. Any pointers on this stuff guys?

I want twin pipes too, if I choose the 535. But have no idea where to get any that fit my application. I have a feeling I will be doing some custom fabbing. For example, buy some unfitted pipes from a company, liek preiceperf, then cut and weld them to fit my sled, which is WAY harder than it sounds. Ill be mig welding this all together, and just hope my welds will not vibrate loose from engine vibration, and I will be using the lowest amperage I can, to prevent burnthrough.

Lots of desisions to make here.....
 
mpsys.ca <-this is the website for the place that makes custom pipes. Your better off calling and ask for steve...talk to him about what you want. This guy has got some talent he turned a beetle engine into a 2stroke!

He also does port and polishing.
 
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