Sell my 750 SX to Fund FX-1?

[joshp]

There are a couple (possibly 3) FX1s for sale in my area. I'm thinking about selling my 750SX to go towards purchasing one of these skis. I know next to nothing about the performance upgrades and modding skis so hoping to get some help here. Is 734 CC a typical engine displacement jump for a 701? Not sure what MSD enhancer means.

I see a common complaint on here is the small pump on an FX1. Is it something that I'm going to notice? Or is this something that only riders of heavily modded skis that are used to crazy pull are going to feel? Put another way, if I jumped on a stock superjet 95 and then road a stock 94 fx1, would I feed a difference in hookup?
Thanks for your time and wisdom!
#1 Aluminum Pole (I think it's AC Racing), rebuilt engine freestyle porting 734 CC, Factory B, MSD enhancer, ADA girdled head $3,500. Engine looks clean. Hard to tell condition of hull exterior.
#2 Aluminum Pole (I think it's AC racing as well), 750CC, MSD, factory B. $4,500 *May have sold
#3 Looks like OEM pole, 701, factory B no foot holds. $2,800. Hull is in good shape engine doesn't look as clean lol.

 

[codybrown]

I love my FX1's and would have a hard time parting with them. If you've never ridden one, the easiest way to describe them is small like a 550 but the power and reliability of a superjet. Both of mine have the stock pumps with Solas props and b-pipes. I'm 6'2" 230 pounds and I can get them to cavitate if I pin the throttlr from a low speed. Once I'm on plane you don't notice it as much. In my opinion a pump swap is wasted time and money. Ride the ski how it was designed and don't ruin it. They only made 1500 of them, and they're getting harder and harder to find, especially in good shape. Just my .02

 

[joshp]

I love my FX1's and would have a hard time parting with them. If you've never ridden one, the easiest way to describe them is small like a 550 but the power and reliability of a superjet. Both of mine have the stock pumps with Solas props and b-pipes. I'm 6'2" 230 pounds and I can get them to cavitate if I pin the throttlr from a low speed. Once I'm on plane you don't notice it as much. In my opinion a pump swap is wasted time and money. Ride the ski how it was designed and don't ruin it. They only made 1500 of them, and they're getting harder and harder to find, especially in good shape. Just my .02

Thanks for the reply! I was curious if my size would be problematic, but sounds like I'll be fine.

 

[codybrown]

Plenty of power. Flatwater without footholds.

 

[bored&stroked]

There are a couple (possibly 3) FX1s for sale in my area. I'm thinking about selling my 750SX to go towards purchasing one of these skis. I know next to nothing about the performance upgrades and modding skis so hoping to get some help here. Is 734 CC a typical engine displacement jump for a 701? Not sure what MSD enhancer means.

I see a common complaint on here is the small pump on an FX1. Is it something that I'm going to notice? Or is this something that only riders of heavily modded skis that are used to crazy pull are going to feel? Put another way, if I jumped on a stock superjet 95 and then road a stock 94 fx1, would I feed a difference in hookup?
Thanks for your time and wisdom!
#1 Aluminum Pole (I think it's AC Racing), rebuilt engine freestyle porting 734 CC, Factory B, MSD enhancer, ADA girdled head $3,500. Engine looks clean. Hard to tell condition of hull exterior.
#2 Aluminum Pole (I think it's AC racing as well), 750CC, MSD, factory B. $4,500 *May have sold
#3 Looks like OEM pole, 701, factory B no foot holds. $2,800. Hull is in good shape engine doesn't look as clean lol.

1-734cc should be the 701 already 2mm overbored.
2-The 750cc is a 701 overbored 3mm or a factory 760 motor
Yes I feel the small pump is a problem. Like Cody Brown said, you can get them to slip easy. What's the point of power you can't put down and enjoy? But yes, they are like a 550 handling wise, which I hate immensely. Some people swear by these things, and I'd take one over an actual 550 any time I had the choice.

 

[joshp]

Plenty of power. Flatwater without footholds.

View attachment 359923

Sold!

 

[joshp]

1-734cc should be the 701 already 2mm overbored.
2-The 750cc is a 701 overbored 3mm or a factory 760 motor
Yes I feel the small pump is a problem. Like Cody Brown said, you can get them to slip easy. What's the point of power you can't put down and enjoy? But yes, they are like a 550 handling wise, which I hate immensely. Some people swear by these things, and I'd take one over an actual 550 any time I had the choice.

Seems like I read something that says, each time you do a top end you're taking a little off. I presume there is only so many topends before there is not enough metal to work with? How many more topends could I do on 734cc?

 

[joshp]

Another thought that popped into my head based on bored&stroked's comment. If I bought 734cc vs 701cc, am I really going to gain anything? There is only so much that can be pushed through the smaller pump that fx1 has. So do I just grab the 701cc that is being sold with factory B pipe?

 

[Citizen]

701 with bpipe > 734 without imo, msd enhancer is a good upgrade too tho...fx1 pump is the weak point, but its way better than your sx regardless

 

[joshp]

Thanks for reply "Citizen", the 734 has factory B as well.

 

[Citizen]

Thanks for reply "Citizen", the 734 has factory B as well.

If the 734 has the enhancer id go that route, u can always upgrade the pump if wanted/needed. The limited bores on a cylinder are not a huge deal really. You can pick up a used stock bore cyl for 150 bucks, get it bored for 50 and be up and running. I think you should still have at least 1-2 bores left on the 734, so as long as you take care of the motor that could be 10+ years easily.

 

[bored&stroked]

Seems like I read something that says, each time you do a top end you're taking a little off. I presume there is only so many topends before there is not enough metal to work with? How many more topends could I do on 734cc?

You can go to 84mm reliably. Most of the time you can do .25mm overbores so that's a lot of rebuilds. Yes, you can get good power gains going up in CC, most people agree an 83mm bore is where its at. If you just bore without porting you probably won't see much gains.

 

[SXIPro]

Displacement is not the be all and end all. A pipe or even porting is far more important than the difference between a 701 and a 734. Id take the 701 since it’s got far more bores left in its future.

 

[joshp]

Thanks for input. Sale ad for 734 says it's bored with freestyle porting. Not sure exactly what that means. Haven't heard back from 701 fx1 seller yet.

 

[bored&stroked]

Thanks for input. Sale ad for 734 says it's bored with freestyle porting. Not sure exactly what that means.

Means they bored a 701 to get to 734cc and widened the exhaust ports without raising them, keeping the operating RPM the same but making it more efficient.

 

[joshp]

Means they bored a 701 to get to 734cc and widened the exhaust ports without raising them, keeping the operating RPM the same but making it more efficient.

Thanks for explanation. Hoping all goes well and aligns with the 734cc. It's near a lake so I'll be able to take it out for a spin. The 701 isn't near water so I'd have to buy based on appearance and compression test.

 

[joshp]

So I figured that I'd look through the fx-1 board to learn a bit about fx-1s. I saw that motobando snapped his driveshaft. That got me thinking. Although the engine parts are going to be accessible, it looks like the driveshaft for the fx-1 isn't shared with the superjet. I did some searching and it appears the driveshaft isn't available from yamaha dealers at least the couple I looked at. The part number is listed but it says not available. Are there any companies making aftermarket driveshafts?

 

[KMN]

You can buy the correct length driveshaft from Jetmaniac here on the forums far cheaper than an OEM would have been if it would have been available. No worries on driveshaft availability.

 

[joshp]

You can buy the correct length driveshaft from Jetmaniac here on the forums far cheaper than an OEM would have been if it would have been available. No worries on driveshaft availability.

Awesome news! I saw jetmaniac mentioned in the other thread but figured maybe he only had left over parts. Couldn't tell if he produced stuff. Thanks!

 

[codybrown]

@Sasquachcrap makes quality custom driveshafts too.