Why people chose Cruiser frames for their builds?

PimpMan

New Member
Feb 10, 2018
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I noticed like 80% of gasoline kits being put on cruiser frames, is there any real advantage of this frames other than having thicker spokes on the rims, and looking more like motorcycle frames?

Why not use say old city bike or MTB frame for example?
 

dogcatcher

Active Member
Nov 11, 2016
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Look back at the original motorized bicycles of the early 20th century, they were also basically cruiser style bicycles. The style allows the motor too set lower, and lower the center of gravity to make them easier to ride.
 

junglepig

Member
Oct 28, 2018
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Georgia
I noticed like 80% of gasoline kits being put on cruiser frames, is there any real advantage of this frames other than having thicker spokes on the rims, and looking more like motorcycle frames?

Why not use say old city bike or MTB frame for example?
Besides aesthetics, many of the cruisers have sturdy steel frames that [I've read] stand up to the beastly engine vibrations of these 2-strokes better than lightweight aluminum frames do. I really like the way they look myself. And they make for a pretty laid-back comfortable ride. That said, I sure wouldn't mind some front suspension on mine.
 

MotorBikeFab

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Sep 5, 2018
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MotorBikeFab.com
Cruisers generally have a larger triangle making it easier to fit an engine. Especially the larger 212cc 4 stroke Predator engine.

Cruisers, however, generally do not have suspension or disc brakes potentially making them more expensive or requiring more mechanical experience.
 

wheelbender6

Well-Known Member
Sep 4, 2008
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Why I built a beach cruiser:
-The beach cruiser has relatively slow steering geometry, so it is stable at motorized speeds. When i put a kit on a mountain bike with a nice chromo steel frame, the quick steering made it feel twitchy around 20 mph.
-A beach cruiser with a tensile steel frame rides smooth. Bumps are absorbed pretty well by the flexy steel and long wheelbase. My motorized mountain bike delivered a punishing ride on the bumps, even though it had a decent suspension fork.
 

WECSOG

Member
Nov 10, 2014
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North Alabama, USA
All of the above, plus the fact that modern bicycles are designed to maximize efficiency in terms of conserving the energy you have to expend. Most of that efficient design and light weight is wasted on a motorized bike, so you might as well use what's cheap and/or looks cool.
 

EZL

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May 13, 2016
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Chenoa, Illinois, USA
Why I built a beach cruiser:
-The beach cruiser has relatively slow steering geometry, so it is stable at motorized speeds. When i put a kit on a mountain bike with a nice chromo steel frame, the quick steering made it feel twitchy around 20 mph.
-A beach cruiser with a tensile steel frame rides smooth. Bumps are absorbed pretty well by the flexy steel and long wheelbase. My motorized mountain bike delivered a punishing ride on the bumps, even though it had a decent suspension fork.
The Sixthreezero bike has a long wheelbase and plenty of room for the 212cc. The CNC mount
is not long enough to couple to the seatpost and the front frame post. The engine has to be tipped
a few degrees to use the mount and to use the smaller CNC valve cover for clearance. The biggest
problem is that darn 1" hub that came with the 7-speed bike in which I got in place of the
single-speed with coaster brake when I ordered it off of Ebay. I guess they thought they were doing
me a favor sending a darn 7-speed in place of the single-speed!
 

javy mcdees

Active Member
Jul 30, 2018
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I am 5.10 and had to raise the bars to get the bike to feel good while steering around tight turns without so much effort. Was a wise move along with a wider bar. but my frame has maybe 5000 or more miles on it and it just cracked the rear lug this morning. I repaired it but now I need to add metal to the area to keep this from happening again. it broke as I was heading out this morning but I welded it quick cause that was not going to stop me today. Been a good frame last 9 months of abuse.
20190607_125332.jpg


bike-mesa.jpg.jpg


the earlier days with the annoying geometry
bike-river.jpg.jpg
 
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Jimmy Bloodmaker

Active Member
Nov 24, 2018
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midwest
I am 5.10 and had to raise the bars to get the bike to feel good while steering around tight turns without so much effort. Was a wise move along with a wider bar. but my frame has maybe 5000 or more miles on it and it just cracked the rear lug this morning. I repaired it but now I need to add metal to the area to keep this from happening again. it broke as I was heading out this morning but I welded it quick cause that was not going to stop me today. Been a good frame last 9 months of abuse. View attachment 101111

View attachment 101114

the earlier days with the annoying geometry
View attachment 101115
add a triangle to the drop outs on each side just in front of where the rim bolts up. will prevent, or at least retard cracking in the future. makes it really tough and spreads the load out on the drop out tubes.
 
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Tony01

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Nov 28, 2012
1,347
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sf bay area
I am 5.10 and had to raise the bars to get the bike to feel good while steering around tight turns without so much effort. Was a wise move along with a wider bar. but my frame has maybe 5000 or more miles on it and it just cracked the rear lug this morning. I repaired it but now I need to add metal to the area to keep this from happening again. it broke as I was heading out this morning but I welded it quick cause that was not going to stop me today. Been a good frame last 9 months of abuse.
It’ll break again. Put a couple gussets as recommended by Jimmy^^^. On one of my builds I went and braced the entire rear end with c-channel and gussets as I was getting a crack every 2 months riding about 1000mi a month. It stiffened the frame up a lot but soon after I snapped my first rear axle. 5000mi is a lot for a 66!
 
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EZL

Well-Known Member
May 13, 2016
262
531
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Chenoa, Illinois, USA
I am 5.10 and had to raise the bars to get the bike to feel good while steering around tight turns without so much effort. Was a wise move along with a wider bar. but my frame has maybe 5000 or more miles on it and it just cracked the rear lug this morning. I repaired it but now I need to add metal to the area to keep this from happening again. it broke as I was heading out this morning but I welded it quick cause that was not going to stop me today. Been a good frame last 9 months of abuse. View attachment 101111

View attachment 101114

the earlier days with the annoying geometry
View attachment 101115
Tony01 has the right idea. I would also use a Oxy/Ace braze weld, the weld looks like a stick welder was used? That's the weak
point in using these bicycles with motors on them and lay off the power in turns helps.
 
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EZL

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May 13, 2016
262
531
93
Chenoa, Illinois, USA
It’ll break again. Put a couple gussets as recommended by Jimmy^^^. On one of my builds I went and braced the entire rear end with c-channel and gussets as I was getting a crack every 2 months riding about 1000mi a month. It stiffened the frame up a lot but soon after I snapped my first rear axle. 5000mi is a lot for a 66!
I have two bikes and one of them is a Micargi "Touch" and the other is the Sixthreezero. The difference between the two is WEIGHT.
The Micargi is a lot heavier, a old-fashion iron bike and it has the 49cc 4-stroke on it with over 3k miles with no problems. The other
one has the 212cc on it and I am babying it since the Predator is a torque machine. I am also watching all the weld points on it.
The Micargi stretch chopper bikes and those areas of the bikes look beefier and might be the way to go with modifications?
I think the next purchase for me will be the "TrailMaster MB200-2 Mini Dirt Bike" and it's not legal for any city use.
 

javy mcdees

Active Member
Jul 30, 2018
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Tony01 has the right idea. I would also use a Oxy/Ace braze weld, the weld looks like a stick welder was used? That's the weak
point in using these bicycles with motors on them and lay off the power in turns helps.
it is a mig welder but no gas used, flux wire. searching now for some steel to weld on. might cut up some lugs off a trash frame to weld on.
will post up what ever I weld on.
binoculars.jpg
 

Tony01

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Nov 28, 2012
1,347
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sf bay area
found some steel laying around the right thickness got it welded on already.

View attachment 101125

View attachment 101126
Nice. Yep that’s fluxcore... like boogers under a church pew. I have a DC fluxcore welder. With a couple upgrades and anti-spatter spray on the visible stuff I get pretty good looking welds.

I don’t know the micargi frames too well. Far as cracks with 212 vs 66 I can say the 66 cracks are mostly from vibration. The 212 doesn’t vibrate anywhere near as much but its torque will break parts. No good cheap options for motors. Wish HF made a 120 or 150. 66s break down often and 212s break parts often.
 
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javy mcdees

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Jul 30, 2018
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yea I had the wire speed to high on one side slowed it down for the other side. I could make it look wonderful but this beater frame has alot of beating on it already. I crashed 3x with it already. countless other small indidents. Everyday something new takes a dump. sometimes I wonder about the head tube just taking a vacation on me.
 

EZL

Well-Known Member
May 13, 2016
262
531
93
Chenoa, Illinois, USA
Nice. Yep that’s fluxcore... like boogers under a church pew. I have a DC fluxcore welder. With a couple upgrades and anti-spatter spray on the visible stuff I get pretty good looking welds.

I don’t know the micargi frames too well. Far as cracks with 212 vs 66 I can say the 66 cracks are mostly from vibration. The 212 doesn’t vibrate anywhere near as much but its torque will break parts. No good cheap options for motors. Wish HF made a 120 or 150. 66s break down often and 212s break parts often.
GOT THAT RIGHT ABOUT A 212cc! I was....going into town this morning and got 3 miles out in the
country and let up on the throttle on a down hill grade (not steep) and heard a pop. I looked down at
the chain and it was missing laying in the road. I thought the keeper might have came off instead the
chain snapped while I started coasting. This Chinese 415 chain is no good and I am going back to the
41 from the BigR farm store, at least it's decent Japanese. The 49cc could stretch the Chinese 415
chain and I've never had it happen with the BigR chain. I am seriously thinking about pulling the
212cc and putting a 79cc on it. I'd like to put a shim on the 79's CVT crankshaft to shim it down
from 3/4" to 5/8",and again I might just go with the 79cc GasBike kit?
 
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