Fito Modena Sport

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trialnerror

New Member
Oct 21, 2014
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cvlt1thanks Dave31

It is my first MB build. It was hard to get the straight chain alignment, with the BB offset, the three inch wide tires. without the chain either rubbing the tire ever so slightly, or the chainstay, had to use one of those hub adapter from http://custommotoredbicycles.com and a wider wheel with heavier spokes, it made the rubber slightly narrower, without bulging at the sidewall so much, and one of those tensioner brackets. now the chain runs free without hitting anything.
Otherwise I luv riding all day on .63 cents of gas. 60-70 miles
 

KCvale

Well-Known Member
Feb 28, 2010
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Phoenix,AZ
It is my first MB build.
It was hard to get the straight chain alignment, with the BB offset, the three inch wide tires.
Yep.
3" tires are tough to get around for direct drive but at least with a 4-stroke you can move the engine.
Bummer you had to sacrifice the rear disc though, that frame simply has no other place for some other brake I can see on mine.

I don't even bother to try to install a second drive chain if the tire is over ~2.5" or if it has a disc brake and the Fito has both, I jackshaft the engine output over to the pedal side.

I have a 4-stroke Fito build in the bay right now, but here is a 2-stroke Fito I did last month, check the tank mount.



I flipped the bottom brackets over and set them on the top bar.
Drilled, tapped and bolted them on so the tank studs went through.
Padded the top bar with a couple pieces of handlebar grip to account for the top bar curve and isolate it a bit.
When it fit right I put some JB weld between the brackets and top bar.
Bolted on nice and then just cut off the remaining tank studs.

It's not as sturdy but pretty.
I had hoped the top bar could be a gas tank so I checked by drilling a hole and filling it water and all it would hold is ~2 cups so not worth it.

You could always still jackshaft your 4-stroke and get your disc back.
SickBikeParts has a 4-stroke shift kit that works your 7G for $200.
Your engine gets to use the gears then too, very cool on these little 4-strokes, you won't even believe the difference, especially riding the miles you do.
 
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KCvale

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Feb 28, 2010
3,966
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Phoenix,AZ
One more tip...
Change your oil often.

A big syringe with ~4" of gas line on the end makes it a breeze.
Suck out the old oil from the filler, then just fill it up with new oil and squirt it in until the level hits the bottom of the cap threads.

Nice clean cheap 5 minute job that will add hundreds if not thousnads of miles to your engines life.
 

trialnerror

New Member
Oct 21, 2014
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wisconsin
The Fito was bought a single speed with coaster brake, no gears. I do though, have 40 plus years with small 4 stroke engines,so maintenance is a blindfolded type thing for me.
though this little engine is made of what looks and feels like what I call Chineseium, so Yes I agree- change oil on a tighter schedule, I use a discarded old vacuum pump (hand operated) for for changing oils on some of my engines that don't have losta room for doing it the Normal way.
I don't have the need for jackshafting it, besides the extra cost, there is more mounting of stuff that could get loose or bearings added on the main sprockets. ahh, just too much more to watch out for. I am a simple person and such ,I like it as bare as possible, being still as safe as I can get it.
 

trialnerror

New Member
Oct 21, 2014
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wisconsin
one thing about the 7G kit is there a freewheel sprocket that will fit the final drive shaft of the transmission? or will the ones for the 4G fit the shaft on the 7G? no one gives an ID measure or shaft size on those free wheel sprockets and shafts they fit. I don't want to go out and spend an extra $75, to get those parts and find they dont fit the 7G trans. http://www.kingsmotorbikes.com/12-Tooth-Sprocket-Free-Wheel.html ,, this is just one example of what i am talking about.
 
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KCvale

Well-Known Member
Feb 28, 2010
3,966
57
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Phoenix,AZ
I missed it not being a 7-speed with rear disc, I didn't know they made that model.
Direct drive was the way to go, just a tight fit.

one thing about the 7G kit is there a freewheel
sprocket that will fit the final drive shaft of the transmission?
or will the ones for the 4G fit the shaft on the 7G?
Yes, there are freewheel output sprockets that will fit, don't have the info in front me, but they are larger and not all that reliable.

Most of the disappointment with the 7G is the clutch bell just being on a bushing and the only freewheel in the whole system, meaning you have pedal the whole drive to the bell on the engine shaft with the engine off.

I tried everything I could think of ditch the bushing for bearings and there just isn't enough room without milling down the output shaft.

The 7G frame just has a big hole where the clutch bell/pulley on the engine shaft fit through.

The 4G and new 10G transfer cases have a bearing housing as part of the frame so a short shaft, pulley and clutch bell are part of the transfer case frame.

This requires the different model HS 142F, it has a short tapered output shaft with the clutch attached.

The new 10G's will come in 2 flavors...

One has a 100T freewheel secondary pulley on a pair of quality Japanese bearings and much better keyed output shaft so you can position the output sprocket where you want, these should be available in the States by summer.

The other version is made for me, the 10G KCK Long Shaft.
That is the going in the 7-speed Fito in the build bay now and I am pretty excited about it.

This is the new longer secondary next to an old 4G as the base remains the same and what it went in.



Note how the clutch bell is part of the transfer case frame, not a bolt in, the secondary however is a bolt in removable.

My version just has an output shaft long enough to reach the right side.



The right side sprocket pair are attached to freewheel bearing, which in turn mounts to the pedal crank axle to isolate the pedals from the sprockets.



I have a pillow block bearing coming for an adjustable right side carrier bearing and designing a new compact base to make it essentially a compact right side drive 4-stroke platform with adjustable tensioner, and a a flexible secondary mounting system to fit a variety of bike frames with a 3-point mount.

I tried this a year ago with that 4G in that first picture using shaft couplers and some spare SBP shaft, bearing and plate parts but that 4G was an 80T so not enough reduction and the couplers simply could not take the torque.



Note how the shaft made it hard to get to the oil filler.
I addressed that as well.

It took a year and a lot of design changes but I have the parts I need to make a pretty sweet little gas engine platform that should actually be more reliable than a left side direct drive, certainly easier to 'make go' with a wide back tire and or disc brakes, with the super double bonus of using the bike gears with the engine and almost no drag when pedaling.

Like I told ya, I am excited about this ;-}
 

wheelbender6

Well-Known Member
Sep 4, 2008
4,059
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TX
The four stroke looks great in your Fito. I would not have thought the thumper would fit that bike until I saw your pic.
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
The four stroke looks great in your Fito. I would not have thought the thumper would fit that bike until I saw your pic.
Ya, S frames rule over V frames for most of what I build.

And the more the bike has on it the better.
$350 seems like a lot for bike until you do the math all the way out to match it piece-meal.

The fake triple tree front shock forks are a joke, but the wheels, headset and seat are a deal @ $350 on a frame that accepts them.

Now if that top bar were just a gas tank... ;-}
 

trialnerror

New Member
Oct 21, 2014
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wisconsin
the worst part of the Fito, was those skinny "alloy wheels" , my friend had came into the driveway, and tried a skid, well actually accomplished a skid, and pretzel'd the rear wheel. that is why I got the good wider steel wheel for it. I think those "alloy wheels" are Chinesium as well. but I do like the non suspension triple tree over a non suspension Huffy or Schwinn fork though. and I have seen soo many of those cheap, and I don't mean inexpensive, springer front forks. I still cringe when I see someone using them. the only front springer that I have "seen" that was good, was on a Ghost Classic, dual springs, and healthy metal, well built, but that would have run another $145. I will stick with the looks and feel of the triple tree. besides I like the idea of having the front disk, too.

10G trans already? What happened to 8 and 9? I was under the impression that the secondary pulley was on an unreliable One Way Bearing. An added unreliable freewheel sprocket 11 or 12 tooth , would be better than just a clutch bell bushing, being the only part freewheeling. they had to be working on the 4G, they replaced the one way bearing on the second pulley with the freewheel sprocket , didn't they? I would get one if I knew it would fit on the 7G shaft. or get the other shaft too if it would fit in the 7G trans bearings.
nobody advertizes the dimensions of the shaft steps, nor the freewheel sprocket width and shaft size.
 

trialnerror

New Member
Oct 21, 2014
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wisconsin
I wonder if the 100 tooth secondary freewheel pulley will fit the 7G shaft? it has a hundred tooth pulley.
 
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KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
I wonder if the 100 tooth secondary freewheel pulley will fit the 7G shaft? it has a hundred tooth pulley.
Maybe, it looks pretty close, I just don't have time to pull the pulley's and measure just now.

The 10G 5 round holes 100TFW is on the left, the pulley mounts to the freewheel bearing which is keyed to the shaft with a bolt and washer to keep it on.

The 7G 3 spoke 100T is on the right, the pulley mounts direct to the shaft with a key, bolt and washer as well, I just don't know if the shafts are the same or not.



The concentric pulley bearing mounts are the same size, 55mm, the much beefier 10G mounts in from the back, the 7G from the front of the base plate. The cutouts in the 7G pulley are to tighten the unit to the base from the outside.



I see no reason the whole units could not be interchangeable.
Besides a much beefier freewheel output for a 7G you get a much friendlier output shaft to work with.



The 7G has a 9T keyed sprocket with no way to keep itself in place.
There is a spacer bushing and a washer/nut combo that is not adjustable.

The 10G has a reversible 9T keyed sprocket with 2 set screws you can put anywhere on the longer shaft you like.
Note that picture has all the extra washers and such Don sent me, I think I have an 10T and 11T dual set screw sprocket as well but I am not to the normal shaft 10G yet, I am playing with my special Long Shaft version ;-}