How fast can my well tuned Spree go?

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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eclark5483
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How fast can my well tuned Spree go?

Post by eclark5483 »

These are just top speed figures of what you should be able to achieve on a Spree if you have no restrictions, proper jetting a good piston, and a properly maintained air/intake setup with a fresh belt and repadded clutch..

I'll break them down by 3 available gears

First we have the 12 tooth (12T) gear found in 84-85' Sprees and ALL Iowa editions all years, In order to achieve these speeds on an Iowa edition, you must remove restrictions. I am only showing speeds up to 8,000 rpm, yes you CAN go faster, but for arguments sake, I am cutting off speed here at 8,000

Image

Next we have the 86-87' model year Spree which sported taller gearing. On a well tuned Spree, you should be able to achieve this:

Image

Now if you went out and invested in some of the higher gears that Taz sells on eBay, here is what you can expect in addition to the Flintstones takeoff.

Image

As you can see, you are adding about 10 mph using the higher gears... yeah, well, expect to LOSE about 10mph on the bottom end without a BBK to help you out, but all in all, that is what should be achievable on your Spree, don't expect much more out of it, and you will be fine.
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Re: How fast can my well tuned Spree go?

Post by Wheelman-111 »

Greetings:

The Final Drive ratio needs to be modified by the "underdrive" of the front-rear pulley diameter ratios. Mousewheels once posted what that is on a Spree somewhere.
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Re: How fast can my well tuned Spree go?

Post by eclark5483 »

Yes, would be nice to have that info, I could correct and adjust for higher accuracy then. Note, the tire size was calculated using 2.75x10 not 2.50x10 which will reduce the final speed estimates.
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Re: How fast can my well tuned Spree go?

Post by Wheelman-111 »

Greetings:

Check in Technical Docs for gearing spreadsheet.
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Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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eclark5483
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Re: How fast can my well tuned Spree go?

Post by eclark5483 »

The tech docs in the wiki are where I got my final drive ratio numbers from.

I referenced the following page in my calculations: http://hondaspree.net/wiki/index.php5?t ... ion_Ratios

I calculated using the biggest tire you could use, which is a 2.75" tire. Yes there may, or may not be a bit of difference in final ratio because of the rpm difference between the engine and back wheel, but it is MUCH more accurate of a figure compared to a CVT based system, which the Spree does not utilize.

The figures I posted can be written off as no more then a "ROUGH GUESS" estimate based on raw RPM to MPH data with the given final drive data. What you SHOULD be able to achieve, in no way reflects what you CAN achieve with proper tuning.

In the end, a Spree is going to do it's best to be a Spree, it's only gonna go as fast as it was meant to. Maybe it thinks you're ugly and that's why it will only do 25. Maybe cut down on the Big Mac's. They ran good then in the 80's, no reason you can't get yours to run well now.
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Re: How fast can my well tuned Spree go?

Post by Wheelman-111 »

Greetings :

So way down at the bottom of that page you linked it says the Spree pulley ratio is 1.8:1. If that's correct, you have your nombers to calculate theoretical top speed. Methinks a tuned Spree or SB with a big carb and pipe is capable of a bit more than 8K RPM, particularly with porting. I am rooting for anyone who tries to the the engine design to its limits.
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Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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eclark5483
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Re: How fast can my well tuned Spree go?

Post by eclark5483 »

Oh for sure it can go past 8,000rpm. I'm just figuring using a typical unrestricted pipe, not a specially tuned one, or other mods to the engine itself. You always here of people going 35 or better on a stock Spree, obviously the rpms (and tuning) have alot to do with that. If you can get your 84-85 past 30 you're doing good, 86-87 past 35 also good. And not very expensive, you don't need any fancy porting or gears, just the right jet and a clean muffler with a good clutch and belt.
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