90 587 general performance improvements

[L.R.TNT]

First of all Hi, I am new to the forum.
Im looking for ways to improve performance on the 90 sp 587 I just picked up. its in near mint shape good compression, no chips or bends in the prop.
I build performance 2 stroke snowmobile engines on the side.
I know a lot about the engine as it is just like the 583 rotax skidoo, so porting, increasing compression, 501 rotary valve, twin carb kit, ect will really wake this engine up to about 70-75hp with the limitation of the exhaust but im just looking for overall performance upgrades.
What prop/impeller do you guys suggest? and ive already got a solas intake grate coming for it as a friend of mine instructed me to do.
Anything else make these things move a little more freely?

Thanks in advance

 

[Bills86e]

up grading compression ect is a con, as this ski is a gas sipper and will last longer if left alone. JMO. Fogging engine after trailoring, recreational gas.
Rinse out and let compartment dry. A great lil ski!

 

[L.R.TNT]

up grading compression ect is a con, as this ski is a gas sipper and will last longer if left alone. JMO. Fogging engine after trailoring, recreational gas.
Rinse out and let compartment dry. A great lil ski!

What is wrong with engine upgrades as long as I add the required fuel to sustain it? Remember the snowmobile version of this engine puts out 110hp....

 

[AdamXP800]

Don't really see the point in modding a 1990 587 ski.



96 XP800!
Keep the 2 strokes alive!

 

[L.R.TNT]

Don't really see the point in modding a 1990 587 ski.



96 XP800!
Keep the 2 strokes alive!

Because I port two strokes, and have a machinist that does my head cutting for me for $20. If I can get my hands on a twin carb setup I could have the hp in your ski for about $100
Keep in mind there are snobby people out there that would say the same to your 96....

 

[mikidymac]

Nothing wrong with the 587 and it is still probably one of the more reliable engines seadoo made and they put it in three seaters too. As far as performance mods good luck. It is much easier to find more performance with more displacement in these.

I would thing one of the few people here that could point you in the correct direction is Matt Braley.

Porting and high compression on one of these old little engines will cause a short life but if you like tinkering you have nothing to loose.

 

[AdamXP800]

Good luck pulling 110 hp out of a 587.
The 587's are great for what they are. They a fun reliable gas sippers. Handling mods I could see doing but anything else I'm not so sure. Not being a snobby 787 rider, just being realistic.

The parts alone would far outweigh the value of the ski. If it's a hobby and time and money are no worry then go for it. I'm sure we would all be interested to see it



96 XP800!
Keep the 2 strokes alive!

 

[L.R.TNT]

Good luck pulling 110 hp out of a 587.
The 587's are great for what they are. They a fun reliable gas sippers. Handling mods I could see doing but anything else I'm not so sure. Not being a snobby 787 rider, just being realistic.

The parts alone would far outweigh the value of the ski. If it's a hobby and time and money are no worry then go for it. I'm sure we would all be interested to see it



96 XP800!
Keep the 2 strokes alive!

I said 70-75hp, the sled makes 110hp now your just taking things out of context.
Been here 5mins it already feels like dootalk.com...

 

[LawnDart]

My 93 spx (white 587) has flame arrestors and a shaved head and I wouldn't call it slow. Been running the piss out of it for 18 years it keeps going. Seems like it has about the right amount of power for that platform.

 

[LawnDart]

Ride plate extension will help keep front down and the pump in the water. Scoop grate will help too though it bogs the motor down keeps you from spinning it.

and get some bars, I've got pro taper schoolboy high:

 

[RodInEscondido]

I said 70-75hp, the sled makes 110hp now your just taking things out of context.
Been here 5mins it already feels like dootalk.com...

So the original post seemed to be soliciting opinions ... I was enjoying the information ... what happened? Sensitive about opinions? On the wrong forum.

what is dootalk.com?

 

[L.R.TNT]

Not sensitive at all, if I've read your opinion once and acknowledged it I don't need to hear it 3 more times. At that point you are a troll. I'm asking for performance options not whether or not I should.
Dootalk is a snowmobile forum for all facets of skidoo snowmobiles, from mountain climbing to watercross to ice drag racing. My real passion...

 

[AdamXP800]

Because I port two strokes, and have a machinist that does my head cutting for me for $20. If I can get my hands on a twin carb setup I could have the hp in your ski for about $100
Keep in mind there are snobby people out there that would say the same to your 96....

No pretty sure you said you could have the hp in my ski. Think before you type all mighty sled man



96 XP800!
Keep the 2 strokes alive!

 

[AdamXP800]

Not sensitive at all, if I've read your opinion once and acknowledged it I don't need to hear it 3 more times. At that point you are a troll. I'm asking for performance options not whether or not I should.
Dootalk is a snowmobile forum for all facets of skidoo snowmobiles, from mountain climbing to watercross to ice drag racing. My real passion...
View attachment 31894

It's your time and money. Go for it sir master sled builder



96 XP800!
Keep the 2 strokes alive

 

[L.R.TNT]

It's your time and money. Go for it sir master sled builder



96 XP800!
Keep the 2 strokes alive

Seriously kid go troll another forum with your 20 year old ski. My sled would roost your ass on water. I asked a simple question and your being a d-bag.

 

[L.R.TNT]

Ride plate extension will help keep front down and the pump in the water. Scoop grate will help too though it bogs the motor down keeps you from spinning it.

and get some bars, I've got pro taper schoolboy high:
View attachment 31889

Thanks for the info, maybe with a few extra hp it won't dog as much.
Anyone bump the timing up and raise the rev limiter in the CDI box?

 

[LawnDart]

Thanks for the info, maybe with a few extra hp it won't dog as much.
Anyone bump the timing up and raise the rev limiter in the CDI box?

Good luck and post it if you mod it out. I'd be interested to see what you can do with a 580. I'm never getting rid of mine.......it gets ridden all day long despite have a bunch of new skis available.

 

[TheMachin0]

i think your on the rite track duel carb set up bump the comp 15-20psi to say on pump gas some kind of pipe if you surf ebay ther is a ton those skis getting parted. you should have no problem collecting cool mod parts. ride mods and pump mods will help that ski a ton. I MY OPINION DO IT DO IT DO IT SHOULD BE A FUN SUPER FLICKIBLE MACHINE MODED JUMPING SPIN FACTORY. don't let those guys get to you it should be a fun project keep posting would love to see what you do and how she works.

 

[96spxpos]

First of all Hi, I am new to the forum.
Im looking for ways to improve performance on the 90 sp 587 I just picked up. its in near mint shape good compression, no chips or bends in the prop.
I build performance 2 stroke snowmobile engines on the side.
I know a lot about the engine as it is just like the 583 rotax skidoo, so porting, increasing compression, 501 rotary valve, twin carb kit, ect will really wake this engine up to about 70-75hp with the limitation of the exhaust but im just looking for overall performance upgrades.
What prop/impeller do you guys suggest? and ive already got a solas intake grate coming for it as a friend of mine instructed me to do.
Anything else make these things move a little more freely?

Thanks in advance

Just out of curiosity..... I recently saw a guy who did a complete rebuild/resto literally top to bottom on like an 89 or 90 SP...and these motors are allegedly tuned for peak performance from the factory..so, as of TODAY, with nothing done to it, what is the current top speed of that ski? I know it probably doesn't have a speedo, as my 95 and 96 doesn't.

 

[L.R.TNT]

Just out of curiosity..... I recently saw a guy who did a complete rebuild/resto literally top to bottom on like an 89 or 90 SP...and these motors are allegedly tuned for peak performance from the factory..so, as of TODAY, with nothing done to it, what is the current top speed of that ski? I know it probably doesn't have a speedo, as my 95 and 96 doesn't.

I'm not 100% sure, i might ask my old man to drop off his radar gun to find out when i put it on the water tonight.
Did anyone make a better exhaust for this thing? And does anyone know if the twin carb exhaust makes more power?
I'm going to squish test it this weekend just to see what kind of compression its supposed to have. If I bump up the comp. for premium fuel only it'll give me 3-4hp.

 

[mikidymac]

Like I said above you need to contact Matt Braley here on this forum. He is very into these older performance skis and mods and has many of the old SeaDoo race engines from back in the day. He would know what you need to make a 580 fast although I think he is more into the 720 and 787 ones.

Another good resource for porting on these would be Harry Klemm at Group K and Watercraft Magic in So. Cal as both of these shops were around back in the day when these things were being professionally raced. Not sure how into the 580 the were but might be able to give you some porting specs now that there is not much happening in the market for the 580.

 

[Coastiejoe]

I have deleted the five posts above this. They did not contribute to the post or the attitude we like to have here at the site.

I just wanted to end this before it went further.


Sent from my iPhone using Tapatalk

 

[mikidymac]

I would like to see where this goes. Lets keep it friendly and help each other out. This is a fun hobby after all.

 

[AdamXP800]

I have deleted the five posts above this. They did not contribute to the post or the attitude we like to have here at the site.

I just wanted to end this before it went further.


Sent from my iPhone using Tapatalk

I will remove myself from this thread. I have nothing to contribute here. Good luck



96 XP800!
Keep the 2 strokes alive!

 

[Robj]

Try and build up the top end of such an old motor will probably just cause the bottom end to fail. I know on some of the older skis it is fairly easy to drop in a 720. But not sure if it can be done on that particular ski. Maybe someone who knows will chime in.