After so many years, this has to be the clearest, most useful video on the subject. I had no trouble following your train of thought. Thank you for making this video! It helped me a lot.
You also need to consider chain tension if you don't want to shorten or purchase a new chain. If you want drastic changes adjust both in the opposite direction. If your looking to increase rpm and gain torque decrease teeth in front and or increase teeth in the back; this decreases top speed. Larger sprocket in the front and or smaller in the rear and you increase top speed but lose torque. See if you can find dyno numbers on your bike and adjust the sprockets to the max torque and horsepower for the rpm range you ride in most. Example - Honda grom: I'm 300 lbs and needed torque and higher rpms, so I dropped one tooth in the front. This allowed me to get up hills and max out the rpms. I may have lost a couple mph of top speed but take off and hill climbing improved drastically. Most likely why the newer models went to a five speed. Front sprockets are cheaper and I would suggest adjusting by one tooth only. If you speed reads off wheel speed your fine otherwise you will need a tune for correct speeds. Check with gps to confirm.
Very well explanation thanx mate and i think this also increases milage of your bike on highway as you are on low rpm compare to stock. actually this makes ratio taller and i personally like taller gear ratio cuz i ride on highways it makes your bike smooth like butter on high speed cruising
Initial calculations are correct but later he is trying by guessing. Here is how to calculate and not guess and try: if you want to reduce rpm by 500 and keep the same speed you need to reduce rear sprocket teeth. 3500/4000 = 0.875 Then 42 teeth sprocket should be reduced to: 42x0.875 = 36.75 rounding it up to 37 teeth. Thank you.
You forget t mention what happens to the torque, whis is important when you hit a slope. If you reduce the teeth on the rear sprocket by too much you will need to gear down more often. The magic is a combination of speed n power which the manufacturer has figured works best. And on the CBR, YOU WILL mess your speedo n odo.....so? Please cover these issues. At the end of the day it all boils down to your personal preferences.
The summary for what sprocket you might want to change to achieve different aspects of rpm power and speed --Front sprokect change bigger faster less rpm smaller slower more rpm bigger less power smaller more power --Rear sprocket change bigger slower more rpm smaller faster less rpm bigger more power smaller less power I recommend changing rear sprockets changing the front can put extra stress on the case drive gear bearing.
Thankful that you made a vid on this subject 🤗 ride safe always sir although this was made year ago it is still helpfull and informative up to this date...
Do not throw your money away changing the sockets. This will only make 2 results: 1. this will improve starting off (launching) 2. this will increase your RPM in top gear at highway speeds. Changing the sprockets is changing the final gearing on your cycle. Changing the final gearing means nothing. What really matters is overall gearing. Overall gearing is everything from the engine to the rear tire. Overall gearing is a affected by these areas: 1. Manual Transmission 2. Drive sprockets (final gearing) 3. Tire size (actually have to change rim diameter to change tire size much) It is a very common misunderstanding that changing the sprockets will mean you'll always have lower gearing. That is not true. You have a manual transmission. That allows you to have what ever gear ratio you want. If you like the power of low gearing then don't shift until redline for all I care. Shifting at redline is not what you really want unless you are drag racing. My point is you can decide how high you want your RPM to go before shifting. If you like low RPM for fuel efficiency shift early and keep your RPMs low. Once you get in top gear you can't shift up any more. That's why I say changing the sprockets will affect the RPM on the highway.
I'm dyslexic, and this was too many numbers for me to comprehend. So short and simple, changing my front sprocket is not an option in my case. However I'm upgrading my entire rear tire/ rim from spoke to mag rim. (Primarily because I keep bending the spoke rims) This forces me to change some mounting adapters, currently I have 42T on the rear large sprocket, Some of the longer steeper hills I can hear and feel the bike struggle to climb. But on flat straight road I'm averaging 22 mph at full throttle. So my dilemma is it wouldn't hurt to have more hill climbing power, but I'm riding on highway roads and can't afford to lose speed. I need to keep up with the slow lane traffic. Most the slow traffic is at least 35 mph. the adapter for the mag rim I'm looking at online is set up with a 36T sprocket. How will the difference between the 42T and the 36T help or hurt me? I am very limited what I can change. This is a bicycle with a 2 cycle motor on it. So I know I'm not any where near what a normal motorcycle has for engine ability.
There's a limit what you can do with changing sprockets. Remember that you still have gears. And each gear has a certain ratio. If you increase the rear sprocket enough, you'l jjust make the 6th gear essentially a 5th gear.
Yeah a lot of people just sell sell sell, they forget about weight x ring rolls tire size ECT ECT hobb made weight punch it's not just go larger and it will have better horse more tourq. Case the guy with a life chain nicer roll less friction and less weight along with proper hobb and tire size you might just get burnt.
If increasing the numbers of teeth at rear end sprocket by 3 Teeth from the stock rear sprocket..do I have to change the chain as a whole or do I need to get a new chain with more linkage?
42/17=2.47 .... change the front for more acceleration so say a 16 , 42/16=2.63 .....263-247=16 ....263/16= irony 16% so changing a tooth on the front down gives you 16% more excelleration. Sod top end , getting theres the fun bit .
Gearingcommander.com is a hugely useful tool. Probably more useful if you understand this stuff, but it does the maths for you. And has a ton of info pre loaded on virtually any bike you could think of
If increasing the numbers of teeth at rear end sprocket by 3 Teeth from the stock rear sprocket..do I have to change the chain as a whole or do I need to get a new chain with more linkage?
If I have a GS750E big bore which makes it a 816cc stock is geared at 14/43 and I want the best top speed but still be able to accelerate at smooth and reasonable time. Can I increase both sprockets up to 17/47? Or does that just cancel each other? With 112 links and 530 chain.
I have a SWM RS500. The standard hearing is 13/47=3.6153846153846 . At general rule one at the front is equal to 3 at the rear. So my my gearing from the factory is pretty good. I just change the front to get a reasonable gear change. The big problem is the bikes ability to hold the gear load. Also it's easier to change the front sprocket out there on the track.. it's all to do with the stall point of your bike. If you own an old school bike that has plenty crank your bike will carry pretty stupid gear ratios. But unfortunately theses late model bike don't and most developed torqued thru engine management systems. I carry a 13 and 15..
bro i have honda cg125..i installed rear lil big tyre and modify with suzuki gs150 shock with front disk...so dafinatly its dry weight got heavy as per normal...so what u suggest me do change front sprocket or rear.??? or both and which size
i think you are mistaken there . is it possible to make bigger sprocket and get more apm or speed ? i think it is the opposite . my question is why in new bike they change the small sprocket to bigger one ?
Hi Nerb1, great vids, enjoying them very much. Quick question, I have a 1190 non R and I need to change chain and sprockets. From your experience would you go unchanged 17/42 or for 16/42 or 17/45, I would like a bit more revs at low speed. Or is it not worth the hassle, thanks!
17/45 for sure. Ive had no loss in fuel economy and its a little nicer at low speed. It actually feels better at highway speed also. 16/42 is almost the same ratio, but wears the chain a bit faster.
Just a quick question. How does the 1190 Adventure get it's speed and distance info?Via a gearbox sensor or the rear ABS sensor? I pose the question because if it's via the gearbox then a change in gearing will affect the accuracy of the speedo/distance recorder. So not only do the revs change for a TRUE 100 kph, but the speedo won't be showing a TRUE 100 kph. I hope I've explained what I merely clearly?
im looking at getting a honda cbr250 rally and im pretty sure its got a 14 tooth sproket on the front and in top gear it sits half way in the revs and id like to lower its top revs in that gear if i was to get one but i dont want to sacrifice get up and go power too much
I think my ninja 250 1994 with 25 inch wheels and a 6 speed manual gearbox that starts redlining at 14k and stops at 16k would go alright with a 36 tooth rear if I could fit it
great video thank you... i do have a question... if i keep the same rear sprocket and i increase 1 t in the front i can have more torque exiting from corners right? my engine will produce a little more torque and higher rpm.
No. If you want more torque, you need a larger difference between sprockets. Increasing the front sprocket is the same as reducing the rear sprocket, which gives you lower rpm for the same speed.
There is way more to it. Tire size, what type pinch power in the rpm, is it hobb done, so weight, so much more goes into it... It's not just go up and down unless your a nub.
Cheers Mia Nerb, good video and very informational. Do you and the other moto vloggers have any plans for coming back down to tassie ( my part of the world ) think you really should, but do more stuff in hobart, like the mountain and other stuffs, cheers mate.
Hey, can i ask? So, i got 250, max speed 160,but i want to cruise at 120-130, but RPM too high...8-9k is too much... So, Q: sprockets, can i lower rpm ny changing gearing with sprocket? (What do i do, bigger or smaller rear)
just fyi...If your sprocket is like mine, there is a "C" and a number after that.... that is NOT the tooth number like the video says... that is the number the manufacturer stamps on it to give the strength of the steel....
Well, i got Hornet 900 and i HATE that it screams in 6th at 100kmh -_- Basicly no difference between 5th and 6th, such an oversight if u ask me, you buy a CBR if u wanna race, and buy CB if you want to commute and cruise, i really dont get why its geared that way. I think the bike will force me to put much less teeth, or sell it and buy another bike that has a long fucking 6th gear. Great tutorial btw, i finnaly get it, i was allways forgetting what does what xd
Thanks! Great video! Can you tell me what it feels like and how bike handles for you with a smaller sprocket in the front?? Like 1 and 2 smaller? Thinking about doing it to my 800gs and wonder how it would be... On trails. Cheers!!
If youre spending a lot of time at walking pace, 1 smaller on the front and several larger on the back will help a lot. The revs will be lifted at low speed, so less stalling and generally less clutch work. You dont want to change too many on the front though... too small a sprocket on the front increases chain wear dramatically, and too big may jam the chain between the sprocket and the engine case.
MX Tex I'd love to, but unfortunately suspension is a black art to me also! Hey MrDuhfactor , can you make a really basic suspension video on what compression, rebound and springs do and what to adjust for certain bike behaviour?
Am very bad at doing math, now tell me my duke 200 needs 0 - 100 as quick as possible , stock one is 14 front , 42 rear .. so whats the best set up do u suggest . Peace ✌
You got it misleading man. Low gearing means that you got less rpm with the same speed of that stock gearing. Ex. At 100kph on stock gearing u may got 5000rpm but if u decrease gearing, on 100kph i assure you its lower 5000rpms
Wrong... lower gearing = higher revs for the same speed. If you’re doing 100kph in 5th gear at 5000 rpm. Then go to 4th gear which is lower your revs will go to say 5600rpm to stay at 100kph. Then go to 3rd gear and revs will be higher again... so lower gear = more rpm for a given speed
Parmeet Lambs What are you hoping to achieve more speed and longevity or more power just drop one or two in the rear if your looking to go a little faster a little farther with less revolutions of engine...
okay so where i live the the 50cc license lets you drive a bike with 50cc and a max speed of 45 kph and the bike i want to get can go with 95 could i change the top speed to go down
i read a blog once and it was recommended, that you never go over or under 10% gear ratio at a given engine power , i went 12% above and my bike actually got slower at top end , what is your take on that
Imagine a car cruising 2k rpm in 5th gear at 80mph. In this imaginary scenario you have a 10 speed and you try to shift to 10th at the same 80mph, you're doing 450rpm and wind resistance slows you down
Dion Mannion Just drop the rear a few teeth for more speed changing both in the same Manor is redundant bigger in the rear slower bigger in the front is faster smaller in the rears faster smaller in the front is slower they're opposites if you go in the same direction they cancel each other out
He forgot about the chain links. If you have 110 link and you take a few off by having a smaller sprocket or adding because of a bigger sprocket, it will also affect the RPMs and Torque.. Tire Circumference Chain Pitch, it all comes in line.. Don't think the factory didn't take all this into consideration.. They have spent millions on engineers to determine what is good for the engine and drive train life.. When you mess with this always remember that your readjusting what the bike is optimized for.. For ex.. My GSXR track bike has the ratio of 18 39. This keeps me in 2nd as my accel, and 3rd to pull, 6 for top speed. Now It's a little slow getting there but I've gained 20 MPH for my top speed.. And great low end cornering accel. It allows me to make some great passes.. And always say WTH did you do to that bike.. LOL.. But over time, it has to be tuned more often, top end spark plugs and timing adjustments, IE.. Power Commander with all the options.. But when I started out, I had none of these items and I was just like you, clueless to the issues I was going to face.. IMO Keep your bike stock on the drive train for longevity, but if you don't care to knock off some engine life.. Just do a nitro setup and that will make up for all your worries.. IM just kidding.. Just take your time and don't get tooth happy.. More teeth equal more acceleration but less top speed, less teeth equal more top speed but less acceleration.. More teeth = more engine wear. Less Teeth = engine working harder and fuel timing adjustments along with other low end adjusting.. But have fun.. and Great VID.. THANKS..
i really dont think the length of the chain or links will affect it. Unless you put a wrong size on,and you can cut it to size yourself,unless you want a big floppy one,however it will have no effect on the ratio. And use the adjustment bolts to get perfect.
jdamage68 True but when you have a motor cross bike that revs out fast with no resistants and has an inefficient top speed dropping a few teeth on the rear sprocket enables you to go many more miles.
Wrong - Period. Length of chain has zero effect on gear ratio. However, length of chain does effect rear wheel motion ratio. Shorten chain, moves rear wheel forward, makes bike more pitch sensitive, harder to transfer rear wheel weight but easier to track low speed corners, and effectively increases wheel rate.
I love shaft drives... basically maintenance free. I had a cx500 and gt550. The xj750 was alright I beleive. I wasnt a fan of the cruiser style, but they were popular. Go for it. You dont need to worry about changing the gearing.
Cheers! That'll help me make a decision for my Tiger. I had mentioned you in a video I posted about 2 weeks ago asking this very question. Thanks for answering even if you didn't know I asked =)
@@Nerb1 hi . My name is Chris. I own a gen5 zx 10r. I am told stock gearing is tall even though Kawasaki claims to have shortened gears 2 thru 6. If I go from a stock 17/39 to 17/41 would that be too drastic just to get a bit more acceleration. Or is a 17/40 sufficient on a gen 5
@@christopheralonge7758 2 teeth smaller on the back is not much... only 5%. I would not be scared to go to a 36 provided you dont regularly try for 180mph.
@@Nerb1 thank you for the reply but I was actually trying to go 2 larger on the rear to a 41 for more acceleration. But I have been told a gen 5 has lower gearing 2 thru six and that going no more than 1 tooth in the rear would be sufficient. Going 2 up in the rearmight be gearing down a bit too much I think. I don't know. I have heard yes and I have heard no. I am confused
Ah, sorry. Somehow i read that you were going 41 to 39. Im blind! Same deal though... 5% is not much. Put on the 41 and see how it feels. You should not need a new chain for 2 teeth and a sprocket is cheap (dont bother with a fancy aluminium one).
