Introvert, njoo kidogo.

Some years back before I began riding motorbikes, I used to do a lot of research on bikes and look through youtube videos and I discovered supermotos. I used to lust after the DT125x but they were only sold in Europe and back then importing was a tall order. I also read about junguz converting their DT125R/REs to supermotos. They changed their rims to 17" ones but the part about changing gear sprockets and shift timing (something like that. Can’t remember clearly) is what I didn’t get. If you do know, would you care to explain? I might just take it up as a project one of these fine days.

https://i.ytimg.com/vi/4_EnljvBv4k/maxresdefault.jpg
Yamaha DT125x

http://onlymotorbikes.com/public/57/yamaha-dt-125-r-1990-moto.jpeg
Yamaha DT125r supermoto mod (frankenstein’s monster)

Edit: NImekumbuka, ni gear ratios ndio zilibadilishwa. For those not in the know, the DT125r/re has 21 inch front wheel and 19" rear and most utilise skinny tires (most are knobby) that are good for offroad riding and puts the bike high enough to avoid obstacles like rocks and little wading. The DT125x uses 17" inch rims (same as street bikes, meaning one can use wide tires (to increase contact surface with the street)) which are better for cornering on streets (and tarmac racing) and getting street oriented tires for this size is much easier street tires for the 21/19 inch combo. (Not that the tires aren’t there but most are dual sport/offroad tires)

Now, where does the gear ratio relationship come in when changing the rim size?

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Pole nimechelewa shuleni.
Nimepata Introvert Jr amekonda mpaka shingo imekuwa refu.
Changing sprocket sizes depends on what effect you want on the final drive ratio.
Basically the same effect as gearing up or down.
See the link below.
Even has a chart to guide.
Supermotos are built for more high end speed than bottom end. The stock configuration of teeth for the DT bikes is ideal for bottom end, hence the need to change the sprockets.
I recently changed the rear rim and tyre of my Tenere from 18 to 17 inch. Now my comfortable highway cruising speed has reduced by 10km/hr so I need a rear sprocket with less teeth.
Same principle as a bicycle derailleur.

http://www.chaparral-racing.com/blog/2011/04/25/adjusting-your-drive-ratio-changing-your-sprockets-for-maximum-performance/

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Mbona hamngetumiana inbox? Kuuliza tu.

For the benefit of other nduthimen my friend.

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Was on a light note. Funny how you call them “nduthimen” aka watu wa kugurumisha nduthi.

Isorait bro.
Leo nimekalia bench ya mbao for 6 hrs halafu jangili imeiba taulo ya kijana yangu na Mrogi Sleeper Beast Bwana Carol hana curse, so sasa nangoja tu mtu anipige sweep nimtolee crayons na Mariamu.

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Anza na mwizi wa towel.

Ahsande sana.

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yo @Jazzman si ununue DT175 uchape nayo tizi. Ama wewe ni cool kid haundeshangi DT kama hio. Io bike inakuanga moto sana, low maintainance cost ,2stroke(old skull kapsaa). Ni guzzler ukicompare na kina captain na Tiger. oil ndio utakua ukiongeza tu. Nduthi ikiona offroad inapata orgasm. plus sound ya DT ni intoxicating wakati unadown shift. Chora na watu wa sirkal upate ex Gk .

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Hapo ndio bado napiga hesabu nichukue bike gani. Nilikuwa na apache nilipata kwa bei ya mboga lakini iliniudhi nikauza. Nafikiria DT175, Shineray 200, UM hypersport ama Raleigh 200

DT 175 itaserve wewe hadi uzeeke. kitu haijui kuharibu engine. Kama utabuy DT ujue lasma itakulambisha mchanga b4 uizoee…dent lasma ikupee.

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Hehehe, hapo sawa. DT it is.

Dents tena, na ndio vile nilikuwa naride bike kama mama mzee

unajua hii bike hua inapick up speed mbio sana alafu tyre ya mbele iapenda kubounce ovyo…traction kaput! sasa ukiwa full throttle upate some soft soil unaware mambo itakuwa tricky kidogo.

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Hehehe.
I don’t know why I am hung up on XT250 or DR250 for a first.
Foe me first bike ilikuwa Suzuki GSX750cc.
Nikaangukia engine ya Bandit 1200cc nikafanya swap. Hiyo karibu iniue mara tatu. Zero to 100 in 2.8 seconds.
After watoi kuanza kukwom nikadowngrade to 600 na 750.
Nikimaliza some milestones hivi karibuni naotea KTM 990 Adventure. Hii tutaisongea kwa bedroom…wife number two.

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Smaller wheels need more revolutions to cover same distance as the larger wheel. Larger wheels need more torque, more tension in the chain while in operation, and less speed. small wheels need less torque, meaning less tension(pull) in the chain while in operation, but more speed. So if the engine and gear assembly maintain the same configuration and speed with a smaller wheel, the bike becomes slower, but a better climber(hills not people). Gear configuration is directly related to the size of the wheel even in vehicles.

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damn! wewe uko sawa mblo izo bike ni za mbirrionaires tu. acha nistick kwa Lane yangu ya thousandaire…for now. my dream is to own a fireblade , haybusa and honda crf250 all under one roof one day… alongside the reliable DT

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Yuko wapi @jumabekavu tulishe mtoto wa watu nyasi??

Hii Sleeper Beast Bwana Carol Mrogi ameshindwa na kazi ya spell casting.
Bure kabisa.

…Don’t fret buddy, Don’t! Pole. There was a time my lovely Dad came to visit me, whilst I was in form one at JKHS … And he almost cried…ask one @bjurmann , how he made in that JOMO high school… It was no joke! …But in the fullness of time, we made it. Be a mentor to the young guy,… WD notwithstanding… :D:D:D

Weh!! Kama at 800cc power to weight ratio ya piki piki na jet ni same, at 1200cc si inavunja shingo on take off? Hizo nitajaribu nikipunguza uoga.

Baaasss. That 990 is a sexy beast. Hiyo na 800GS ndio my ultimate bikes.