_JOE_

~SPONSOR~
May 10, 2007
4,697
3
Hey guys, we picked up a 2001 Mini Adventure not running. Was told it needed piston and cylinder. Got it home and pulled it down and it appears to have a brand new piston. Makes good compression by feel but I haven't gauged it yet. The issue seems to be that there are a few different piston/cylinder combos used on these Franco Marini engines. After a little research I believe it's an S5-E, which is an iron bore. I read that the iron bores run solid pistons where the S5-GS has a plated bore and runs a piston with a window. The piston in this bike has the window. It will try to start but dies right out. I've been through the carb and it's spotless. Fuel flows great and it actually pushes fuel into the pipe but the plug comes out almost dry. Makes a good, strong, blue spark but won't fire. I'm stumped and looking for someone for who can help me verify what piston design I should have in it. I'd just buy the KTM top end kit but I'd be upset if the piston is the same as what's in there. Even if someone knows anyone I could call to try and sort this out would be awesome! Thanks guys!
 

helio lucas

~SPONSOR~
Jun 20, 2007
1,020
0
Hi joe,
i am not familiary with those engines but they have a reed valve or is the piston skirt that controls the inlet timing?
i am asking this because if is the second option, then the piston must have no windows, and i do remember older engines (morini brand) had piston port inlets.

hope it helps.
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
It has no reeds. I'm 90% sure it has the wrong piston in it. I found a place selling pistons for LEMs that has some knowledge about these engines and they said the same, if it doesn't have reeds it takes a solid piston. Guess I'm going to make sure the ignition is good and order a top end kit. Hoping that's all it needs, these boys are sooooo ready to ride this thing, lol.
 

helio lucas

~SPONSOR~
Jun 20, 2007
1,020
0
cool thing is top end parts are cheap... :cool:

good luck on the ignition thing... ;)
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
I need to get it cleaned up and take some pictures. It's super clean. The only thing that doesn't look almost new is the rims. They got rusty from sitting for the last 6 or 8 years. The tires, plastic and grips are all in like new condition. They said it doesn't have more than 20 hours on it and I'm starting to believe it. Not sure what happened that made it quit running as the bore doesn't look like it was seized up or anything. Oh well, hopefully it runs good with the right piston in there. In the meantime we've split it down to the bits and are cleaning and greasing everything. Even the brake shoes and drums show very little wear. Looks like we found a good one if I can get it running, lol.
 

High Lord Gomer

Poked with Sticks
Sep 26, 1999
11,790
34
I had a couple of older ones and hated the Dellorto carbs on those things. Had to jet them for the morning practice, then again for the first moto then again for the afternoon moto. Very finicky. Mine were 95 and 96, I think. Hopefully that was sorted out by 2001.
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
It's got a Dellorto 1412. Only the main jet can be changed. It's a funky little carb for sure, the slide setup is something else, lol. The mid 90s ones had the air cooled Morini motors right?

It's going back together now. Got the suspension all cleaned and greased and back on the frame. I sure wish the rims weren't all scabby, this thing is looking like it just came out of the crate. The factory grease had turned to glue, I had to pound the front axle out, thought it was going to be a rusty mess. Turned out that it was just glued in there with dried out grease.
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
Here's some pics....

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helio lucas

~SPONSOR~
Jun 20, 2007
1,020
0
it looks very close to my old malaguti grizzzly that i have converted to a 125 engine :yikes:

very nice bike!!! they will like to ride it, it´s pretty fast... how are they on the pw and ttr???
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
They've outgrown them. They've been outriding the suspension for a while now and thier butts are several inches above the seats when they stand over them. The KTM is a little taller but won't last long. It'll do for next season but then it'll have to go to sis. I'm going to be in the market for a newer model Senior Adventure in the spring. Those are quite a bit taller. They can stay on the seniors until they're ready for 65s.... :yikes: At that point I'll have to go to a riding school to keep up with them, lol. ;)
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
They're pretty pitted. I'm thinking flat black powder coat. My brother in law can do smaller items at his house so I'll probably go that route.
 

Bonehead

LIFETIME SPONSOR
Mar 15, 2001
406
1
Sorry to say Joe but it needs an ignition Poloni makes one for it.$150.00 I had to put one on my kids bike Ran like a top for years after.
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
I think the ignition is ok, but we'll find out for sure once I get the proper top end fitted. I can't imagine it would be bad considering it has very little run time on it. It makes a nice blue spark. I couldn't find any specs to test it so we'll have to wait and see......
 

Bonehead

LIFETIME SPONSOR
Mar 15, 2001
406
1
My doughters had about 1 1/2 hrs on it and would start run and die in the same way. I hope it is just the piston but the one i had also had a great initial spark keep us posted
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
Will do. I'm positive now that it has wrong piston so that's step one, lol. Motosport has one for $125 if I need it. Do you remember if there's a gap spec for the coil to rotor? I set it at 10 thousandths for now. I'm still looking for a manual for it.....
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
And the headache continues......got the top end kit today. Piston, cylinder, pin and circlips are all there but no rings! They're going to get a set from KTM then overnight them so it'll probably be friday before we see them. They offered to credit me whatever the cost is if I could find them locally but I called every KTM dealer within 200 miles of here and no one has them. This thing is turning a giant pain in the arse! If it doesn't run when I put it together I swear I'm going light it on fire, lol. I feel terrible for the boys, they were so excited when the parts got here and then bam.....disappointment. :(
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
Well, she's up and running! Starts pretty easy but doesn't seem to pull very hard. Honestly I think the PW is quicker. I'm not sure if it's a clutch or a tuning thing or if it's just not that fast. I'm going to try to get some jets and I'll inspect the clutch. If that doesn't turn up anything I think we'll just sell it in the spring and get a newer model SR Adventure with the 3 shoe clutch and reed valves. At least you can run an SX50 clutch in those to get them to hit harder. The boys were a bit disappointed with the power.
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
Ok, so we ended up picking up an 05 sx pro senior last weekend. It fits them well and runs alot stronger than the mini adv. The mini seems to be running better the more they ride it so I'm going to let them have at it and see how it goes. So far they haven't been out of the yard with them but if the weather holds out we're going out on sunday. We swapped the clutch washers out for springs in the sx so it's more rideable for them and they're loving the extra power. My one son just doesn't like the foot brake thing. He wouldn't ride the crf because of it and says he feels like he cant stop good enough on the sx. I'm sure he'll catch on sooner or later. Here's a short video of them riding at the house....

http://s893.photobucket.com/albums/ac139/_joe/?action=view&current=006-1.mp4
 

helio lucas

~SPONSOR~
Jun 20, 2007
1,020
0
damn, they are getting fast every day. :cool:

about the foot brake, i still have that problem today after riding 15 years. i started and learn to ride on a scooter with hand back brake and had riding a lot of bmx.
the trials bike has helped a lot on instinct and smoothness...
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
They are getting pretty damn fast! I used to be able to put some ground on them on the 50s in the yard, now they try to bang bars and get around me, lol. The SX is about perfect for them. It fits them great and has the kind of power they wanted. It's awesome watching them carry the front end out of corners! That video was the second day they rode it, they've progressed alot in the last couple days and seem to be alot more comfortable with the spring clutch setup than they were with the washer stacks. I'm excited for next season! ;)
 
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