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Old 02-02-2009, 07:07 AM   #1
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Default Helical vs. straight cut diff gears???.....

I downloaded the manuals for RC8, MBX6, 8ight 2.0, D8, XRAY 808 and MP9. I noticed that only RC8 and D8 use helical cut diff gears n pinions, MBX6 has it as an option, the rest come with straight cut diff gears. In theory, helical cut gears should be better and can handle higher stresses (assume same material) than their straight cut counter part. Has anyone experienced the difference in performance on the track for these two types of gears?

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Old 02-02-2009, 07:07 PM   #2
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Caster Racing switched from regular cut gears to heli/spiral cut gears because we were having issues. The new ones are much better and stronger from what we have seen. All ours come with the new gears now also.

From a 1.1 car standpoint, the theory is that being cut that way adds more surface area and gives approximately 20% more surface area and strength. I have no idea how I remember that......lol.
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Old 02-02-2009, 07:16 PM   #3
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Originally Posted by ganymede View Post
MBX6 has it as an option, the rest come with straight cut diff gears.
the mugen uses helical cut gears standard.
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Old 02-02-2009, 09:21 PM   #4
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Jammin' X2 uses helical cut gears as well, X1 did not. Drivetrain spins more smoothly and easily on the X2.
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Old 02-03-2009, 12:35 AM   #5
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From what I've seen, straight cut gears are more reliable, and are more forgiving on gear mesh.
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Old 02-03-2009, 06:05 AM   #6
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Originally Posted by o.s. power View Post
the mugen uses helical cut gears standard.
the user manual that i downloaded from mugen's official site clearly shows that they are straight cut gears... did mugen put in helical cut gears in later "updated" batches but did not revise the drawings in their user manual?
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Old 02-03-2009, 06:31 AM   #7
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Must admit havent checked manual but my MBX6 which was in the first batch to hit the UK has helical gears.
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Old 02-03-2009, 09:54 AM   #8
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In 1:1 cars, high-end manual transmissions use Straight cut gears, because they have less parasitic drain, resulting in more power to the wheels. Therefore, this would be the same for other scale cars.
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Old 02-03-2009, 10:55 AM   #9
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I have the original USA version MBX-6 and it does have helical/spiral cut gears, not sure on the manual though.

Difference, helical/spiral cut gears seem smoother and stronger.
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Old 02-03-2009, 11:08 AM   #10
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might be wrong but straight cut gears in 1:1 cars is used for its ease of use and simplicity plus the benefit of race cars not needing to use a clutch in a race application and the durability by having less parts like the sychromesh etc.

Must say helical is a big improvement over straight cut and as mentioned it lends to having more surface area and aids in a smoother mesh.


http://en.wikipedia.org/wiki/Gear#Helical_gears
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Old 02-05-2009, 07:32 AM   #11
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Quote:
Originally Posted by slow coach View Post
Must admit havent checked manual but my MBX6 which was in the first batch to hit the UK has helical gears.

MBX6's instruction manual (manual_e0050.pdf) page 3...

mugen might have changed the later batch to helical cut diff gears...
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Old 02-05-2009, 08:03 AM   #12
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Straight cut gears produce less friction= less heat= more power.
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Old 05-26-2011, 03:25 PM   #13
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I know this is an old thread but I had a question on gears. Do you shim both types of gears the same in terms of how tight? Do you run the Straight cut more or less loose then Helical?

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Old 05-26-2011, 03:30 PM   #14
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Quote:
Originally Posted by CarCrazy View Post
From what I've seen, straight cut gears are more reliable, and are more forgiving on gear mesh.
I agree. It's easier to set mesh, and also easier to clean.....I have never had any issues with durability with strait cut gears, it's myth....They just throw helical in there to make it sound better, it's a sales pitch...Pitch haha...
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Old 05-26-2011, 03:33 PM   #15
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I have used both and havent had issues with either. But you do have to pay more attention to the spirial cut ones.
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