Swapped the Chinaman for the Italian

GoldenMotor.com

andy b.

New Member
Jul 14, 2010
55
0
0
PA, USA
My attempt at a sub-$300 motorbike didn't quite pan out as I was so fed up with the Grubee motor after a month of screwing with it, I went ahead and ordered a Morini S6E. I got everything installed enough today that I could take it for a short ride.

This was yesterday evening after I had finished up the motor mounting.


I still need to weld up a top mount, but that is simple enough.


I got the chain installed today and welded up the exhaust header. Right now the header is just the part that bolts to the engine and then it comes out on a 90 degree curve and sticks out to the right. It looks kind of cool, but it is a little too loud for anything other than test riding. I picked up one of the small pipes from a KX65 to use for my exhaust and the chopping has already begun. :)

I also had to bend the cranks to clear the engine. I was surprised at how easy it went once I figured out how much heat I needed to apply and where. Oxy-Acetylene is your friend. And the pedals even ended up straight and level.

A few observations. The new engine fired up on the second kick right out of the box. I think I have about 5 miles of attempted starts on the Grubee and it still never ran. To start the Morini now all I have to do is give it a half of a lazy kick and it roars to life. NICE!!!!

When the engine is idling and I am standing still on the bike, there is no noticeable clutch drag and the bike sits there in neutral. A slight twist on the throttle and the clutch already starts to engage. In several of the posts I have read on the Morini clutches, it sounded like they needed a good bit of revs before they engaged. All I can say is on my new engine, this does not appear to be the case. Maybe it will change as the clutch wears in, I don't know.

It is relatively warm, and the engine seems to start fine with no choke. I'm running a pretty rich mixture, about 30:1, of Motul synthetic oil, so I think the engine should be getting enough lube at start-up even with no choke. I used to run the Motul at 50:1 or less in a mildly modded Banshee 350 I had years ago, so I hope this little moped engine will run with the same once broken in.

I've been pedaling up to about 6 or 7 MPH before giving enough throttle to engage the clutch, and then helping it along to about 10 MPH with no problem. There are a few short hills in front of my house I was riding on, and I had no problem doing 15-17 MPH up them. I didn't want to get too crazy with a new engine. I realize this engine is only a 3HP model, but it feels like it will do 25 MPH easily, which is all I'm asking of it. I'm running a 52 tooth rear sprocket and this seems like a good size for my use.

I really only have one question, if you've read this far. What are some tips for routing the exhaust? It looks like you need to find that sweet spot of not hitting the front tire, not hitting your feet, not hitting the ground, and not burning your leg on it. It almost has to run up near the top tube on the left side due to the layout of the engine. Tomorrow's project is figuring out how to run the exhaust in some sort of sane manner.

andy b.
 

Goat Herder

Gutter Rider
Apr 28, 2008
6,237
20
38
N.M.
Looking good good.(^)

Morini's get there power from the rpm's. The power band of that three horse power engine uses a lighter clutch springs. That's why it engages at a sooner rpm. I believe that is a 6000 rpm engine. Completely different animal from the bigger hp engines..
 

corgi1

New Member
Aug 13, 2009
2,272
3
0
KCMO
That is a nice looking set-up,,secure the top of the head to the frame so ti dosent twist,, and is the gear down from the engine crankshaft too the out-put sproket the same as the china motors?
 

Easy Rider

Santa Cruz Scooter Works
Jan 15, 2008
2,145
7
38
Nor*Cal
The bike looks great but please read the front fender threads. My buddy had a Schwinn like yours but red and his front fender broke off and launched him, breaking a few of his ribs
 

andy b.

New Member
Jul 14, 2010
55
0
0
PA, USA
Goat,

Thanks for the info on the clutch. That does make sense, since I know the S6E def revs less than the other S6 models. I think it still revs up near 9k though. There was some other Morini engine (a little 28cc one) that was something like 1HP and only revs to 6k.

corgi1,

If you mean is the reduction ratio in the gearbox/clutch assembly on the Grubee the same as on the Morini, that I am not sure of. I should probably measure it to find out since I now have one of each (unfortunately on the Grubee). Since I never had the Grub running, I can't say for sure, but from what people have posted and what the guy at Herdan.com told me, I think the ratio on the Morini is higher, plus I think the Morini engine revs higher than the Grub. That is why I think my 52 tooth rear sprocket seems like a good choice for me. I don't need to do 50 MPH. :)

Easy,

I hear you on the fenders (and read your posts on them). That is the very next thing I am going to modify after getting the exhaust mounted. I'm thinking stainless button-head screws with locknuts should look nice and work good. I'll probably make a new bracket out of a small piece of stainless as well. The screw that holds the lower mount for the rear fender already fell out somewhere in my attempts to get the Grub running, so that also needs to be replaced.

andy b.
 

corgi1

New Member
Aug 13, 2009
2,272
3
0
KCMO
I was thinking the gear ratio would be important too set it for hills as well as flat land,50 is a nice size for extra power on hills w/a china motor and if the motor too sproket gearing is higher then this one should pull from lower speeds ,less pedaling (I think I said that right)