60cc piston for the Spree?

Post by **noiseguy** » Wed Sep 08, 2004 3:43 pm

Hey, does anyone know anything about a 60cc piston for the Honda Spree? I've seen a few posts that refer to it, but can't find a Honda part number or supplier. It's supposed to be buried on this site:

http://www.network54.com/Hide/Forum/26489?it=0

which has a really terrible seach interface, and over 100 pages of entry to go through. Other posts I've seen for it are "you can get it only through me" posts, which means that it's probably some Honda part # that has circulated but isn't commonly known. Anyone?

Jerry · Post by **Jerry** » Wed Sep 08, 2004 7:26 pm

To start with, the Spree has a 49cc engine. There are mods for different bikes that will take it to 70cc.
Going from 49 to even 60cc is going to require more than a new jug/head/piston/ring set.
Carb for instance and fuel flow. Air intake, exhaust - all different.
If anyone advertises that they are the only ones that can supply the parts....be suspicious. If it were a kit and if in fact it worked, EVERYONE would advertise it and sell a bazillion of them.
Use caution.

Post by **noiseguy** » Wed Sep 08, 2004 9:51 pm

Yep, I'm comfortable with that. Exhaust, intake, carb, and probably reed block. Most of the above is buildable. Just not the jug, head, and pistons. I have access to a machine shop and technical help, but not a foundary. So what parts interchange with this Spree engine?

Jerry · Post by **Jerry** » Thu Sep 09, 2004 9:27 pm

I've always stuck to stock parts. As far as interchanging with different bikes, I honestly couldn't tell you. Sorry
What little that I did for mods ended up not working the way it should so I just scrapped the idea. Of all the things that I have tried, only a standard automotive belt by Bates (I think) was wider (1/2 in vs 1200) and that gave a higher top speed. Even then I had a * of a time getting the right size belt with the waves in the center to allow greater flex. It's on one of my bikes now and the next time I take it apart, I'll post the belt number. Jets, exhaust, etc - no joy.

Jim · Post by **Jim** » Thu Sep 09, 2004 11:24 pm

Good idea about the belt, I would like to know the number the next time you take it apart

Post by **noiseguy** » Tue Oct 12, 2004 3:44 pm

You can remove your belt and take it to the auto parts shop. They can measure it and (usually) give you an equivalent length back. The increased width of the belt does the same thing as the "pulley mod" listed above does for the stock belt i.e. removing .03" from inner pulley.

The belt length needs to be close, but if it's slightly shorter it will effectively increase your ratio for more top speed, as the rear clutch will be spread farther apart (smaller effective diameter.) Problem is that you can only push this so far, as eventually you won't be able to launch from a stop. That's the problem with 1-speed gearing. Top end speed is gained while sacrificing your ability to launch.

If you can't visualize it, remove the LHS cover and look at the belt drive, you'll see what I mean.

If anyone experiments with this I'd love to hear what you find out.

Kikwear · Post by **Kikwear** » Mon Nov 22, 2004 12:17 pm

I'm going to be doing the pulley mod this week. This is going to reduce my ability to move from a stop?

Post by **noiseguy** » Tue Nov 23, 2004 8:38 am

Since you're increasing your ratio, you should launch slightly slower, although you gain top speed. You'll also be launching at a lower RPM, which doesn't help either.

In practice, I didn't notice a difference on launch speed. Pretty slow anyway you go.

Shane4188 · Post by **Shane4188** » Tue Nov 23, 2004 12:22 pm

I'm inclined to stick with all stock spree parts. Jerry makes a point when he says if there was a kit that worked, there would be thousands for sale. Plus it makes my 1993 Jeep Grand Cherokee seem fast. LOL

Kikwear · Post by **Kikwear** » Tue Nov 23, 2004 1:28 pm

I'm all about the stock parts too. I was originally thinking about milling the head but I'd rather just do the pulley mod.

Tippmann98 · Post by **Tippmann98** » Tue Nov 23, 2004 4:25 pm

Not me, im gonna put a .50 oversize piston in. Then get modify it to get more intake and more outtake, a size 70 jet, clutch mod, and an aftermarked air filter. Im hoping it will do at least 40. Sort of keep up with my Aprilia.

Kikwear · Post by **Kikwear** » Wed Nov 24, 2004 1:01 am

Is the bike that stable at 40? I mean these are 10" tires.

Post by **noiseguy** » Wed Nov 24, 2004 11:29 am

Unless your Spree's compression is off, requiring new rings/piston, a + .5mm piston isn't going to get you any more performance, as the displacement bump is minimal.

There are scooters sold with 10" tires that will do 55 MPH. The Spree chassis isn't set up for 55 though. Even 45 would probably be pretty scary. Just look at the front "shocks," they're just springs with some friction damping. Rear shock doesn't have much control either.

A steering damper and a better rear shock would make it safer at higher speeds. Swapping in an Aero 50 frontend of the same vintage (which sounds like is a bolt up) would be a good idea as well, as this fork has a better design.

Once someone gets a 45 MPH Spree built, we'll talk more about chassis mods.

Kikwear · Post by **Kikwear** » Wed Nov 24, 2004 12:01 pm

I see the Spree and the Aero were produced in overlapping years. What's the difference between the two?

Post by **noiseguy** » Thu Nov 25, 2004 1:13 pm

The Aero 50 and Spree have at least the following differences: Aero 50 has a variator on the front pulley vs fixed ratio on Spree, and a 3 gear rear diff vs. 2 gear on Spree. Later Aeros look like they may have a different intake tract and reed valve.

Jim had a friend that swapped a Spree frontend into an Aero. I'm guessing the Aero swap would also require a new fender for the Spree.

Overall, the engines look more similar than they are. I would need to pull apart an Aero motor to find more similarities.

BTW, later Honda Elite 50 and 80 motors will bolt into the Spree with some mods, and have aftermarket support. This would probably be the way to go for performance. The Spree is really light (80#,) less than the Elite but with a much more primative chassis.