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Old 11-18-2012, 08:04 AM   #1
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Default whats the difference btw rally and on-road

whats the difference btw say a nova kappo .21 rally ($309) and a nova kappo .21 ($343)?

specs are identical yet the rally is $30 cheaper

and how does the sport n21r7 stack up to either of these
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Old 11-18-2012, 09:37 AM   #2
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From what i seen 1speed trans for shaft and the its the belt driven ones.
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Old 11-21-2012, 04:07 AM   #3
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nice
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Old 11-21-2012, 09:40 AM   #4
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Quote:
Originally Posted by 1966ss View Post
whats the difference btw say a nova kappo .21 rally ($309) and a nova kappo .21 ($343)?

specs are identical yet the rally is $30 cheaper

and how does the sport n21r7 stack up to either of these
I believe that the stroke may be different between the two. Usually, onroad engines tend to be short stroke whereas offroad engines tend to be longstroke. This places the powerbands in different locations in the power spectrum (short stroke is usually more high mid to top end while long stroke is usually more low end to middle mid-range).
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Old 11-21-2012, 08:11 PM   #5
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Originally Posted by JLock View Post
I believe that the stroke may be different between the two. Usually, onroad engines tend to be short stroke whereas offroad engines tend to be longstroke. This places the powerbands in different locations in the power spectrum (short stroke is usually more high mid to top end while long stroke is usually more low end to middle mid-range).
?
I alway's have had good luck using long stroke /high port .21's in my onroad car's
and Short Stroke. 3 - 5 port motors in my offroad buggys.

??
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Old 11-22-2012, 12:22 AM   #6
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?
I alway's have had good luck using long stroke /high port .21's in my onroad car's
and Short Stroke. 3 - 5 port motors in my offroad buggys.

??
Hey, I still don't have the long/short stroke thing figured out yet. Was hoping to get someone that knows more about it on here to answer 1966ss's question. With all these experts out here, someone should have been able to help him by now.
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Old 11-22-2012, 07:26 AM   #7
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copy and pasted right off novarossi's website
bore and stroke are the same. im assuming the principle we use in our real cars for drag racing hold true here. This is a larger bore/shorter stroke will rev higher and make more power up stairs while a smaller bore/longer strock yielding the same cubic inch will make more low end grunt and not rev as high. this priciple i know well. my question is what is the difference btw these two motor that spec the same. why is one labeled rally? and why is the rally 35$ less?

KAPPO.21

Displacement: 3,49 cc
R.P.M. (max power): 38.000 RPM
Practical range: 6.000-44.400 R.P.M.
Bore x stroke: 16,26x16,80 mm
Sleeve: 7 ports
Rear ball bearings: steel
Front ball bearings: steel
Crankshaft: 14mm - turbo
Carburetor: aluminium - 9 mm - slide
Glowplug: Turbo (C6TGF)
Exhaust position: rear
Starting: -
Weight: 336 g
Fuel type: 25% nitro

KAPPO.21 RALLY

Displacement: 3,49 cc
R.P.M. (max power): 38.000 RPM
Practical range: 6.000-44.400 R.P.M.
Bore x stroke: 16,26x16,80 mm
Sleeve: 7 ports
Rear ball bearings: steel
Front ball bearings: steel
Crankshaft: 14mm - turbo
Carburetor: aluminium - 9 mm - slide
Glowplug: Turbo (C6TGF)
Exhaust position: rear
Starting: -
Weight: 336 g
Fuel type: 25% nitro
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Old 11-22-2012, 05:08 PM   #8
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There is only slight timing difference. The rally version will hit max power slightly sooner than the onroad version. That is all.


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