Honda Spree and Elite 50 Forums

hmm i don't really like the idea of taking my head to get milled

bc117 wrote:hmm i don't really like the idea of taking my head to get milled

So buy another head and machine it.

good idea will other heads like spree or elite fit? what about porting the stock cylinder?

I have 5 spare heads, one for my Spree and the BBK. Another one for my Aero 50 for just a for a compression boost. Then 2 spare heads for my Aero 80 and one for for the Aero 125's.

The Spree head has a different part number than the Aero. However they use the same head gasket, so it will physically fit. But you need to check the chamber size as it could be too big or small, changing the compression ratio.

sounds good i am currently opening up the intake manifold and ran across this http://www.hondaspree.net/phpBB3/viewto ... f=8&t=2957 , thats the sb50 intake+reeds vs. the spree but it looks much bigger than my aero's too, so will the sb50 intake and reeds fit my 85' aero and would that yield more lowend or topend?

bc117 wrote:sounds good i am currently opening up the intake manifold and ran across this http://www.hondaspree.net/phpBB3/viewto ... f=8&t=2957 , thats the sb50 intake+reeds vs. the spree but it looks much bigger than my aero's too, so will the sb50 intake and reeds fit my 85' aero and would that yield more lowend or topend?

It will bolt up but not to the Aero airbox. The Aero intake is longer than the Spree or SB50.

The following are SB50 on the left and Aero on the right.





The Aero uses the same reeds as the late Spree ('86-'87). The SB50 reeds are different and only used on the SB50 and SB50p.

Yeah and I know the pictures are Wheelman quality, sorry.

just ported the case+intake, and went back and opened snd raised the exhaust port all the way, then removed the base gasket but still not enough, i am leaning ever closer to the bbk but now i am wondering how much can i over bore the stock cylinder. Could i get anywhere near 60cc+

Greetings:

Surely the stock jug has enough meat to get to 46 or 47 mm, or 63-65cc.
The tricky part will be finding a piston to match te stock rod.
VT carries a 46mm Tai kit, and DayWot has/had a Polini 47. Both bolt-on with modded head. The Polini is a very good quality setup and the port geometry is done correctly, Italian-a-style.

ya i definately dont want to go over 100 dollars for a bbk so im just thinking i could pick up a cheap 46-47mm piston then take my cylinder to a shop and have em match it to the piston p.s. what size is the wrist pin

Greetings:

10mm, methinks. An alien piston's pin location with respect to the crown and skirt, as well as the port cutouts will be hard to match up with the cylinder.
VT's bore kit isn't far off your 100C budget.

good point how big could i go with hondas largest standard overbore size

Greetings:

Typically an overbore piston is only fractionally (0.5-1mm) larger than stock.
While technically "bigger", the performance gained from 49 to maybe 51cc is negligible.
Some things are fun to try, but if you want my advice, start with a $100 VT kit and mod from there.
Better still, try the $200 DayWot Polini. With gears it's a 60-MPH setup. And reliable.

BTW, what'd you mean by raising the exhaust port "all the way"?

i followed these steps http://www.hondaspree.net/phpBB3/viewto ... f=8&t=7843 http://datsunroadsterranch.com/scooter/export06.jpg , i have yet to properly test out the modifications but in the putting around i did still lacked the wheely popping power i was after so maybe i should try 1k clutch springs or something

by the way i have the belt, clutch and clutch bell off a gy6 can i do the zx trans mod?

just put some polini natural clutch springs in and went for a ride they increased my take off alot but it feels like my clutch is now slipping or something cause sometimes ill take off really fast it wants to lift the front up and other times i just slowly accelerate up till about 20 before it starts accelerating normal