Creeper gear? Any way to increase gear ratios from stock?

The "Pimp my Ride" section for Soviet bloc bikes. Everybody seems to have their own custom add-ons, modifications & accessories. Share your tips and post pictures of them here.
Forum rules
This is the place for topics concerining modifying and accessorizing your Ural or Denpr.
User avatar
Eric N
Comrade General
Comrade General
Posts: 858
Joined: Sun Jul 24, 2016 3:26 pm
Location: Westminster, Colorado

Creeper gear? Any way to increase gear ratios from stock?

Post by Eric N » Wed Oct 05, 2016 10:07 pm

I have a fast bike, don't need the Ural for speed, I'd actually prefer to lower it's speed a little and give it a granny gear.

Has anyone retrofitted higher gears to make the bike more crawler friendly? I'm cool with a top speed of 55mph but feel the stock first gear is a tad high for steep loose dirt and I'd rather not burn up a clutch.

I have from what I can tell stock gears on a 2001 Patrol 650. I lifted the rear tire and the driveshaft turns just shy of 5 spins for one spin of the wheel, I'm pretty sure it's the stock 4.62 final drive and my shifting pattern seems to match the stock range. She'll go 65mph no problem, I don't need it to go that fast.

I'm ok with the current gear spacing but wouldn't mind a higher gear in the final drive to make the bike a little slower and better for climbing offroad.

Has anyone swapped gears to either put higher gears in the tranny or a higher final drive? If so, where did you get the parts?

I tried searching for forum but seems people want to go the other direction and try to lower the gear ratio for highway and I want to go the opposite direction.
2018 Gear Up
2013 Retro Solo
2001 Patrol - Sold

User avatar
Bacon Andy
Comrade Colonel
Comrade Colonel
Posts: 481
Joined: Mon Sep 05, 2016 12:33 pm
Location: SW Michigan

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Bacon Andy » Wed Oct 05, 2016 11:30 pm

:lurker:
Eric N wrote:I have a fast bike, don't need the Ural for speed, I'd actually prefer to lower it's speed a little and give it a granny gear.

Has anyone retrofitted higher gears to make the bike more crawler friendly? I'm cool with a top speed of 55mph but feel the stock first gear is a tad high for steep loose dirt and I'd rather not burn up a clutch.

I have from what I can tell stock gears on a 2001 Patrol 650. I lifted the rear tire and the driveshaft turns just shy of 5 spins for one spin of the wheel, I'm pretty sure it's the stock 4.62 final drive and my shifting pattern seems to match the stock range. She'll go 65mph no problem, I don't need it to go that fast.

I'm ok with the current gear spacing but wouldn't mind a higher gear in the final drive to make the bike a little slower and better for climbing offroad.

Has anyone swapped gears to either put higher gears in the tranny or a higher final drive? If so, where did you get the parts?

I tried searching for forum but seems people want to go the other direction and try to lower the gear ratio for highway and I want to go the opposite direction.
80ish Kawa 650 LTD gone
76 Guzzi 850T-3 needs to go, parts bike
2004 Night Train, fast
2013 GU, loaded.
WTH? I've never had an original idea!

User avatar
Bilgekeeldave
Commissar
Commissar
Posts: 3533
Joined: Thu Jul 19, 2007 12:04 pm
Location: Western Washington

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Bilgekeeldave » Wed Oct 05, 2016 11:59 pm

Nope, they are what they are.
Dave

RAMCO-Dnepr MT-16

gobium
Order of Victory
Order of Victory
Posts: 14797
Joined: Wed Sep 07, 2011 2:06 pm

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by gobium » Thu Oct 06, 2016 12:18 am

If there is a way mr. cob would have done it all already.
Ural in not atv

User avatar
jaybird
Order of Lenin
Order of Lenin
Posts: 1475
Joined: Thu Jul 01, 2010 4:41 am
Location: The foothills of the Forked River Mountains, West Barnegat NJ (Do It In The Pines!) 08005

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by jaybird » Thu Oct 06, 2016 10:39 am

Thats the holy grail of Ural driving, if you could get a little lower gearing for off road, and a little higher gearing for highway travel, these rigs would be "perfect".
The easy way to get a little lower gearing for off road would be to switch to a shorter wheel/tire combination, for example an 18" wheel with a 3.10x18 tire.
BTW, Extended driving at 65mph is a sure death for a Ural engine, I find that engines last longer if you don't exceed 4500 rpm (4000 rpm it will last "forever") for extended periods.
Install a tachometer, it's more reliable and useful than the speedometer.

Happy trails,
Jaybird
Last edited by jaybird on Tue Oct 11, 2016 12:22 am, edited 1 time in total.
2005 Gear-Up, Mr. Nat_ural 108,000+ Kilometers and counting
2013 Retro, Black beauty, AKA Lucky "13"
1995 Olive Tourist
1975 Enfield Diesel Bullet
2008 Enfield Bullet 500
1974 BMW R 75/6
Etc.

gobium
Order of Victory
Order of Victory
Posts: 14797
Joined: Wed Sep 07, 2011 2:06 pm

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by gobium » Thu Oct 06, 2016 11:10 am

Best solution
FB_IMG_1474293892154.jpg
You do not have the required permissions to view the files attached to this post.

User avatar
lomax
Order of Lenin
Order of Lenin
Posts: 1003
Joined: Sun Feb 09, 2014 2:47 pm
Location: Westminster, CO

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by lomax » Thu Oct 06, 2016 11:17 am

Just drop a tooth on the front sprocket. :lol:
84 R100RS LE,14 Ducati MTSGT,14 Hyperstrada, 73 850 Commando, 78 CT90, 14 Ural, 74 Eldorado police, 64 R50/2, 13 TR650, 01 DRZ400E, 94 900SS/CR, 01 200EXC, 77 HD XLCR https://lomaxcm.smugmug.com/

rivers
Hero of the Soviet Union - 2018
Hero of the Soviet Union - 2018
Posts: 8793
Joined: Sat Jul 24, 2010 10:04 pm
Location: west WA

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by rivers » Thu Oct 06, 2016 11:36 am

gobium wrote:Best solution
FB_IMG_1474293892154.jpg
Van you have a secret source for Zundap reduction boxes? :)
Joe
014 GU
"I'm lost but I'm making good time."

User avatar
Tin Man
Commissar
Commissar
Posts: 10172
Joined: Mon Nov 19, 2007 2:15 am
Location: Johnson County, Texas, USA

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Tin Man » Thu Oct 06, 2016 11:41 am

Many of have dreamt of a first gear that is 1/2 lower and a top gear 1/2 higher..... :foilhead: .....sadly it is nothing but a dream....... :(
Mike
2007 GearUp (Arctic #1)
130/45 jets, KTM rock solid mirrors, Delaware Dave's outstanding trunk lock, Mr. Cob's most excellent skid plate, Cycra Probend smashproof hand guards, Duro strong like bull 307's, RotoPax damn near bulletproof fuel cans, MKIII all but water proof air box and Dimples super duper magnetic drain plugs all around...oh yeah, and a manual fuel petcock.

.........if you see something that needs doing, just do it........

User avatar
LRP
Hero of the Soviet Union - 2018
Hero of the Soviet Union - 2018
Posts: 2366
Joined: Sun Sep 28, 2008 8:25 pm
Location: Deltona, FL

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by LRP » Mon Oct 10, 2016 9:45 pm

Drive components could not withstand the added torque. Just look at the diameter of the drive splines and driven splines in the wheel hub.
Ural has a chance to beef up the final drive now that they have disc brakes on the pusher wheel--they don't have to size the drive hub
and driven hub to fit inside a drum brake assy.
Army Bird Dog Pilot, Nam.
2018 CT
Traded '08 Patrol

19 previous motos

User avatar
Eric N
Comrade General
Comrade General
Posts: 858
Joined: Sun Jul 24, 2016 3:26 pm
Location: Westminster, Colorado

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Eric N » Mon Oct 10, 2016 11:03 pm

Hi LRP,

I don't know the evolution of the drive components, I haven't seen a change in parts numbers for final drive from my 650 to the modern 750's but I haven't really looked. If it's correct that the modern components are interchangeable with the final drive parts on my 650, the drive components would be able to withstand a 20% increase in torque.

The specifications I've found for my 650 suggest it produces a max 34.7 foot pounds at 4800 rpm, a 2016 produces 42 foot lbs at 4,200 rpm.

I understand it might be unwise to increase the torque on the components above 42 foot lbs until there is a redesign, my engine is not that powerful.
2018 Gear Up
2013 Retro Solo
2001 Patrol - Sold

User avatar
LRP
Hero of the Soviet Union - 2018
Hero of the Soviet Union - 2018
Posts: 2366
Joined: Sun Sep 28, 2008 8:25 pm
Location: Deltona, FL

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by LRP » Wed Oct 12, 2016 4:32 pm

Hi Eric,
You have to take into account the reduction of the transmission and final drive in relation to torgue. By example, at 3750rpm torque peak of 37 lbft
of my 08 Patrol, 1st gear provides a reduction of 3.6:1. The 1st gear output, not counting frictional losses is 1041 rpm and 133 lbft.
Then going through the 4.6:1 final drive, 225 rpm and 611lbft arrives at the roughly 2" diameter splined drive hub.

Lets say you install a 7:1 final drive. It would deliver 931lbft. to the hub.

LRP
Dick
Army Bird Dog Pilot, Nam.
2018 CT
Traded '08 Patrol

19 previous motos

User avatar
Burt1713
Hero of the Soviet Union - 2018
Hero of the Soviet Union - 2018
Posts: 667
Joined: Sat Sep 26, 2015 8:46 pm
Location: Olney Illinois

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Burt1713 » Wed Oct 12, 2016 5:26 pm

I don't know how something like this would last, but it would give you a crawler geared bike if it would fit in place of the driveshaft.

http://www.speedwaymotors.com/Howe-Raci ... 24447.html
2017 cT "Woody Moose"
2002 Ural solo bobber (work in progress) “Symphony of Destruction”
1997 Sportster "Scarlet Speedster"
1984 Honda Interceptor "Cornfield Express" (Gone)

User avatar
Eric N
Comrade General
Comrade General
Posts: 858
Joined: Sun Jul 24, 2016 3:26 pm
Location: Westminster, Colorado

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by Eric N » Wed Oct 12, 2016 5:59 pm

Hi LRP,

I think we're talking about two totally different bikes.

In my initial question, I'm using a 2001 Ural 650. If the drive train components haven't really changed over the years, and the old drive train components are interchangeable with the new ones, it could in theory take a 20% increase in torque without problem. That's not a 7:1, more like a 5.5:1 using the lower output of a 650 engine. I suspect if you crunch numbers using the 650 torque data and a 5.5:1 and match it to the stock setup on your bike, the numbers won't be too far off.

I have a co-worker who was previously in the gear making business. I'm going to ask his thoughts on a 7/37 gear set.
2018 Gear Up
2013 Retro Solo
2001 Patrol - Sold

GregAus
Comrade General
Comrade General
Posts: 519
Joined: Mon Oct 13, 2014 1:13 am

Re: Creeper gear? Any way to increase gear ratios from stock?

Post by GregAus » Thu Oct 13, 2016 12:28 am

Available gear ratios for pre-Hertzog Ural gearbox. Some Dneprs had a 4.11 first gear and a guy named (I think) Tattoo Pluto fitted a 4.11 gear to his Ural. You can't fit that ratio to an electric start gearbox.

Gear ratios               
        I               3.60                 3.20
        II              2.28                 2.08 1.71
        III             1.71                 1.56 1.30
        IIII            1.30                 1.19 1.00
        Rev 4.36        

Final Drive        3.89                 4.62                          

http://www.sovietsteeds.com/forums/view ... hp?t=11511 discusses the topic

Post Reply