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  #3111  
Old 02-14-2012, 11:28 PM
5-7HEAVEN 5-7HEAVEN is offline
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Default Re: what did you do to your motor bike today?

Quote:
Originally Posted by Skarrd View Post
Got a 40t #25 gear in today for the pocket bike jackshaft.

6t-40t = ~6.67:1 reduction
10t-44t = 4.40:1
40t-28t = .70:1
final drive in 1st gear = 20.53:1

should work out for some nice gearing.
Interesting combination...pb engine, midframed w/shift kit.

What gears are you running? 7/8-speed cassette? 3-speed internal hub?

FWIW, my gear ratio in 1st gear is 46.32:1. It's like a granny gear for climbing steep hills, and 8th gear is highway gear @ 15:1.

Your 1st gear is 20.53:1.

My 6th gear is 20.45:1, and I'm @ 30-something mph in that gear.

You might want lower gear ratios.

Last edited by 5-7HEAVEN; 02-14-2012 at 11:53 PM.
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  #3112  
Old 02-14-2012, 11:30 PM
5-7HEAVEN 5-7HEAVEN is offline
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Default Re: what did you do to your motor bike today?

[QUOTE=happycheapskate;364457]A lot of low-end bikes use a rear derailleur with its own hanger built in. (usually found on bikes with long horizontal dropouts, using a solid axle).

Thanks for the lead, happycheapskate. I'll look into that, as soon as the frame arrives.

Aleman's Quote: Nice frame, 5-7. However, I don't think those guides are for a derailleur. There seems to be no derailleur mount on that frame.
Looks like guides for an internal hub's shifter cable. Although, one doesn't often see internal-hub bikes with V-brakes...

You might be right. I'm glad you guys are here to point things out. I'm not sure myself and will keep researching.

[QUOTE=DaveC;364452]$31 might have been the bid you won at but $92 for shipping needs to be added in, too Is it that expensive to ship to Hawaii? Or did the seller stab you on the shipping? I know that some sellers add their minimum to the shipping but that just seems a bit much

Dave, it is EXTREMELY expensive shipping to Hawaii, but sometimes I get a break. No such thing as free UPS Ground shipping. Some sellers won't even sell or ship to Hawaii buyers. I have a drop point in California. Sometimes it's cheaper to ship there, then reship to me.

I got lucky. I WAS gonna eat the $92 shipping, but the vendor offered to ship via Parcel Post(slow boat), which will cost me $42. Frames are tough, so it should handle bad handling.

For me, $73 for a new steel quality cruiser frame with v-brakes and wide dropouts is my wish come true!

I was willing to be stiffed for $175 for this Diamondback. The new Roadmaster frame w/coaster brake on ebay would've cost me $150.

Last edited by 5-7HEAVEN; 02-14-2012 at 11:44 PM.
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  #3113  
Old 02-15-2012, 12:04 AM
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happycheapskate happycheapskate is offline
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Default Re: what did you do to your motor bike today?

If shipping is that expensive, and customs allows, you might invest in a small boat with an efficient outboard, and make a side job out of taking packages from the mainland to customers on the islands. $92 ! !!! ouch!
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  #3114  
Old 02-15-2012, 12:07 AM
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The_Aleman The_Aleman is offline
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Default Re: what did you do to your motor bike today?

Quote:
Originally Posted by happycheapskate View Post
A lot of low-end bikes use a rear derailleur with its own hanger built in. (usually found on bikes with long horizontal dropouts, using a solid axle).
Sure, I'm familiar with those. But that bike pictured never had one mounted, and if you were to mount a hanger like that, you'd compromise the strength of the dropout. That bike pictured is more suited to internal hubs.
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  #3115  
Old 02-15-2012, 12:39 AM
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Default Re: what did you do to your motor bike today?

Quote:
Originally Posted by 5-7HEAVEN View Post
Interesting combination...pb engine, midframed w/shift kit.

What gears are you running? 7/8-speed cassette? 3-speed internal hub?

FWIW, my gear ratio in 1st gear is 46.32:1. It's like a granny gear for climbing steep hills, and 8th gear is highway gear @ 15:1.

Your 1st gear is 20.53:1.

My 6th gear is 20.45:1, and I'm @ 30-something mph in that gear.

You might want lower gear ratios.
I'm running a 7 speed cassette. i'm gonna switch it to my 34t 1st gear one which will give me 24.93:1 in 1st.

running a 24" tire, that will put me at
1st=17.2 mph at 6000 rpm 34t 24.93:1
2nd= 24.3mph at 6000 rpm 24t 17.60:1
3rd= 26.6mph at 6000 rpm 22t 16.13:1
4th= 29.2mph at 6000rpm 20t 14.67:1
5th= 32.5mph at 6000rpm 18t 13.20:1
6th= 36.5mph at 6000rpm 16t 11.73:1
7th= 41.7mph at 6000rpm 14t 10.27:1

I've heard these motors can reach 10k rpm range, and from the design i've seen i'd say that's rather feasible. the cylinder has 4 transfer ports (two large ones on the sides, and 2 small auxiliary ones opposite of the exhaust port.) not to mention the crank case is amazingly tiny compared to the china girl's crank case.

i'm also thinking that since these little motors put out 3-ish horse power that it shouldn't have much of an issue with running it like this.
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  #3116  
Old 02-15-2012, 02:17 AM
5-7HEAVEN 5-7HEAVEN is offline
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Default Re: what did you do to your motor bike today?

Quote:
Originally Posted by Skarrd View Post
I'm running a 7 speed cassette. i'm gonna switch it to my 34t 1st gear one which will give me 24.93:1 in 1st.

running a 24" tire, that will put me at
1st=17.2 mph at 6000 rpm 34t 24.93:1
2nd= 24.3mph at 6000 rpm 24t 17.60:1
3rd= 26.6mph at 6000 rpm 22t 16.13:1
4th= 29.2mph at 6000rpm 20t 14.67:1
5th= 32.5mph at 6000rpm 18t 13.20:1
6th= 36.5mph at 6000rpm 16t 11.73:1
7th= 41.7mph at 6000rpm 14t 10.27:1

I've heard these motors can reach 10k rpm range, and from the design i've seen i'd say that's rather feasible. the cylinder has 4 transfer ports (two large ones on the sides, and 2 small auxiliary ones opposite of the exhaust port.) not to mention the crank case is amazingly tiny compared to the china girl's crank case.

i'm also thinking that since these little motors put out 3-ish horse power that it shouldn't have much of an issue with running it like this.
JMO, I think you're in for a disappointing ride with those gears. You will definitely know this when you're stopped at the bottom of a steep ramp or hill, and try to climb it.

Ask me how I know this.

With a 3-ish hp 10,000rpm engine, you'll be making less than 2hp @ 6,000rpm.

If your engine has 10,000rpm capabilities, you'll be shifting @ 10,000rpm, not 6,000rpm. No one shifts 4,000rpm short of the redline.

My 2.8HP Tanaka 47R engine is rated @ 7,000rpm redline. With the pipe, I'm shifting @ 8,000rpm or a little less. If I'm putting around, I shift @ 5500rpm.

Here's how your gearing works @ high rpm.

First gear.....22.9mph @ 8,000rpm.....28.6mph @ 10,000rpm.
Second gear.....32.5mph @ 8,000rpm.....40.6mph @ 10,000rpm.
Third gear.....35.4mph @ 8,000rpm.....44.3mph @ 10,000rpm.
Fourth gear.....38.9mph @ 8,000rpm.....48.7mph @ 10,000rpm.
Fifth gear...43.3mph @ 8,000rpm.....54.1mph @ 10,000rpm.
Sixth gear.....48.7mph @ 8,000rpm.....60.9mph @ 10,000rpm.
Seventh gear.....55.6mph @ 8,000rpm.....69.5mph @ 10,000rpm.

You will run out of road in second gear.

In comparison, here's my gearing @ 7,000rpm redline and 8,000rpm:

First gear.....12.1mph @ 7,000rpm.....13.9mph @ 8,000rpm.
Second gear.....15.9mph.....18.1mph @ 8,000rpm.
Third gear.....17.9mph.....20.5 @ 8,000rpm.
Fourth gear.....20.6mph.....23.6mph @ 8,000rpm.
Fifth gear.....24.3mph.....27.7mph @ 8,000rpm.
Sixth gear.....27.5mph.....31.4mph @ 8,000rpm.
Seventh gear.....31.7mph.....36.2mph @ 8,000rpm.
Eighth gear.....37.5mph.....42.8mph @ 8,000rpm.

Last edited by 5-7HEAVEN; 02-15-2012 at 03:19 AM.
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  #3117  
Old 02-15-2012, 02:25 AM
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GearNut GearNut is offline
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Default Re: what did you do to your motor bike today?

I smashed it many times with a hammer!





Well..... maby they were carefully placed blows on the left edge of the rear fender with a 10oz ball peen.
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  #3118  
Old 02-15-2012, 02:39 AM
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Default Re: what did you do to your motor bike today?

LOL GN. I think we all have had occasion to do some "smash meditation" Even if it does not work, ya do feel better for several seconds. Right up until ya consider the cost.

C'mon, tell the truth, did ya beat that fender in to submission?
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  #3119  
Old 02-15-2012, 03:46 AM
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happycheapskate happycheapskate is offline
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Default Re: what did you do to your motor bike today?

I politely disagree. The derailleurs with integral hangers brace against the dropout nicely, and the anti-rotation pin can couple with a top-hat nut (usually come with them) or conventional nut and washer, behind the dropout. You do not have to drill a hole in the dropout for the anti-rotation pin. If you have a good eye and steady hand, you can weld a hanger tab on any standard dropout. I put one on a BMX when I was a kid, and made a 7speed BMX chopper that worked nicely.

http://cdn.schwinnbikes.com/catalog/product/cache/55/image/457x300/9df78eab33525d08d6e5fb8d27136e95/s/_/s_2011_S4032_slv_13.png
New Schwinn Wayfarer 7speed cruiser with integrated-hanger r.d.

Quote:
Originally Posted by The_Aleman View Post
Sure, I'm familiar with those. But that bike pictured never had one mounted, and if you were to mount a hanger like that, you'd compromise the strength of the dropout. That bike pictured is more suited to internal hubs.
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Last edited by happycheapskate; 02-15-2012 at 03:53 AM.
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  #3120  
Old 02-15-2012, 03:53 AM
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Ibedayank Ibedayank is offline
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Default Re: what did you do to your motor bike today?

5-7heaven



you prolly have this frame and its a 7speed
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