Sprockets

[m in sc]

i use an angle grinder myself. (actually a cut off wheel) i don't like pushing a rivet through a roller, as it spreads out the ID of the roller.
cut the head off the rivet , and then near the back part of the chain where you want to remove links, cut the outer plate in half, and then take the front half of the link plate off. zero load on the chain link you are going to run. I'll actually be doing this tonight.

 

[SLO]

Take the number of rear sprocket and divide by number of front sprocket. That will tell you the ratio. 47 tooth divided by 13 tooth front means for every 3.6 turns of front sprocket the rear will turn once. The speedometer will be slightly off unless you go up on tire size. 244 Shinko 3/0s will actually run faster than the speedometer reads,and the bike will also be going faster in your case,if you can wind it up fast enough. Unless you live in south Florida,I doubt you will.

OOPS, I wasn't thinking. It is not a 47 tooth rear. Anyway,mine probably runs better than anyone else's out there the way I have it set up. It ain't bragging if it is fact! I do believe that pure gas with a little Marvel Mystery oil actually give it a boost you would not notice if it was a bigger displacement. All I can say is try it in a speed run on same road in the same conditions. Maybe chain slack,alignment,tire pressure,outside temp,chain lube, or a good batch of gasoline. Try it and see,it will not hurt anything,it even stops the sound like it is going to fly apart rattles when winding the shit out of it. I think we are talking about a 320 to 1 ratio,and if you think that will F it up,I believe it might prevent it if you are in extreme conditions,such as extreme heat (pavement) heat ,heat for whatever reason is like a snowball going down hill in snow covered field.

 

[SLO]

OOPS, I wasn't thinking. It is not a 47 tooth rear. Anyway,mine probably runs better than anyone else's out there the way I have it set up. It ain't bragging if it is fact! I do believe that pure gas with a little Marvel Mystery oil actually give it a boost you would not notice if it was a bigger displacement. All I can say is try it in a speed run on same road in the same conditions. Maybe chain slack,alignment,tire pressure,outside temp,chain lube, or a good batch of gasoline. Try it and see,it will not hurt anything,it even stops the sound like it is going to fly apart rattles when winding the shit out of it. I think we are talking about a 320 to 1 ratio,and if you think that will F it up,I believe it might prevent it if you are in extreme conditions,such as extreme heat (pavement) heat ,heat for whatever reason is like a snowball going down hill in snow covered field.

Oh yeah MC, that was my intent. Spreading the JOY,I could even see the smile on your face before I posted. Actually I give you much of the credit for the helo you provided me when I started on this journey. I took the DR 200 out last night for a spin after putting on a 40 dollar Amazon carbon fiber exhaust. I think they are all made in the same factory and are marketed under different brands. I could not believe the difference,and shed about 12lbs from that OEM piece of crap.Got a NIBBI pwk 32 carb to put on it,just had a little problem with the air box boot being old and not pliable. 1999 model. New brakes,front and rear,as well as wheel bearings,Shinko 244s. I could not believe just changing the exhaust would actually wake it up with stock carb.Waiting on a UNI filter and new engine flange Amazon! VROOM VRRRROOOOOM.

 

[m in sc]

i run a 28mm NIBBI on my xr150L, its a great little carb

 

[johnny125]

Placed a webike order for a 15t front and 36t rear sprocket, (14,38 standard)

Some question if anyone knows:
will changing from the oem 14t front to 15 cause the abs fault or is that only a byproduct of going to the smaller 13t? Is the ABS controlled by ecm or its own module?

 

[dmonkey]

There is an ABS modulator, separate from the ECM. It compares vehicle speed from the countershaft to front wheel speed at the pulsar ring on the front brake rotor. I suspect that any significant change in gearing could still fault the ABS, which can be compensated for with a speedometer healer and some math to get the settings right. With the change you're doing, I would not expect it to be an issue but haven't tested to confirm.

 

[johnny125]

There is an ABS modulator, separate from the ECM. It compares vehicle speed from the countershaft to front wheel speed at the pulsar ring on the front brake rotor. I suspect that any significant change in gearing could still fault the ABS, which can be compensated for with a speedometer healer and some math to get the settings right. With the change you're doing, I would not expect it to be an issue but haven't tested to confirm.

Thanks for the informative reply!

Ill report back on how it goes.

 

[johnny125]

^ an update to the 36 tooth sprocket. Ran the rear 36 with the stock 14 front for a few hundred miles, looking for a few more mph top end. Results were mixed, the bike did feel less stressed on the hwy but top speed did not improve, got a loss of about 2mph (gps) and all-around made it feel more lazy. Put the standard size 38 tooth back on last night. Haven't tried the 15 tooth front yet. Even with the bbk theres not enough power to do much more with it.

 

[SLO]

^ an update to the 36 tooth sprocket. Ran the rear 36 with the stock 14 front for a few hundred miles, looking for a few more mph top end. Results were mixed, the bike did feel less stressed on the hwy but top speed did not improve, got a loss of about 2mph (gps) and all-around made it feel more lazy. Put the standard size 38 tooth back on last night. Haven't tried the 15 tooth front yet. Even with the bbk theres not enough power to do much more with it.

I could have saved you a lot of work. You can look at the hp/torque curve,or just accept that you gotta wind the shit out of it. I put a 13 tooth in front before I did the Yuminashi 143 cc BBK ,opened the exhaust,a 150 Honda injector,run Shinko 3/0 front and back.The 13 tooth in front was a must before anything else. Open the air intake,and the Yuminashi kit included a 238 cam. I live in the mountains,and it makes a difference,but the 13 tooth in front is a must! I have over 5000 miles on it,and oil changes and type oil will save you the headaches ot following the experts.

 

[ol mike]

Are the liteweight rear JT Sprockets available for the Honda Trail?

I've messaged JT twice and not received a reply.
Any help please !! ?? ..

 

[MyersJ2]

They are slow to reply for sure. Remember they are thousands of miles away from the states (assuming you are here).

As far as light weight I'm not sure what you are wanting. I just installed my second set of JT's (11 miles on my first set). I'm not sure youd want a lighter set. The theorhetical power gain will be so minimal and then you are replacing it much sooner. And the design of the rear of this bike is cheap. Not exactly my most fun bike to work on. *hint, use zip tie(s) to hold your brake caliper in place while reinstalling wheel. The increased longevity of forged steel is worth it. My trail is a '22. JT does NOT make the stock sized rear sprocket for it. You have to go with the newer size for the updated bikes. Its only 1 tooth difference though. I ended up ordering from amazon but https://sprocketcenter.com/ is a good resource too.

amazon B001AVOKAO rear, B0068OCK3C front, and I used this chain both times B07XWPZ5RP

 

[dmonkey]

JT (Jomthai) Sprockets do make a rear sprocket for the 2022 CT125.
JTR269.39 is 39T and stock gearing for the 2021-2022 JA55. The 2023+ JA65 has 38T on the rear instead.
Note that the stock sprocket nuts will not sit flush on the JT sprocket, but you can buy other nuts that will:

Chain and sprockets

I just bought a CT125 2023. As you know it has a 14" front sprocket and a 39" rear sprocket. I am going to use this cycle for hunting 80% of the time and have realized that the stock configuration is not going to work. I want to be able to able to go thru the woods at a walking speed or close to...

hondatrail125.com

Having done that, if you are still going to run stock gearing I'd recommend just sticking with the OEM parts. I've since gone back to them after switching to a RK GC sealed chain. The OEM rear sprocket has a ring on it that helps reduce chain noise, and though it's not necessary, the JT doesn't have that.

 

[ol mike]

They are slow to reply for sure. Remember they are thousands of miles away from the states (assuming you are here).

As far as light weight I'm not sure what you are wanting. I just installed my second set of JT's (11 miles on my first set). I'm not sure youd want a lighter set. The theorhetical power gain will be so minimal and then you are replacing it much sooner. And the design of the rear of this bike is cheap. Not exactly my most fun bike to work on. *hint, use zip tie(s) to hold your brake caliper in place while reinstalling wheel. The increased longevity of forged steel is worth it. My trail is a '22. JT does NOT make the stock sized rear sprocket for it. You have to go with the newer size for the updated bikes. Its only 1 tooth difference though. I ended up ordering from amazon but https://sprocketcenter.com/ is a good resource too.

amazon B001AVOKAO rear, B0068OCK3C front, and I used this chain both times B07XWPZ5RP

On the JTSprockets website , sprockets section they show light-weight sprockets [scroll down] made of C45 steel . I'm not talking about going to aluminum. I'm wondering if the light-weight just has more metal removed from the design?
With the Trail 125 producing a mere 8+hp every little thing will help it perform better. I'm at 5,214' elevation.

JT Sprockets: Sprockets

 

[dmonkey]

If you're looking to shed weight from the final drive, you can also downgrade to lighter duty #420 sprockets and chain like all the other 125cc Honda mini motos in the USA use.

CT125・ハンターカブのチェーン＆スプロケットの交換方法｜必要な工具・作業手順・注意すべきことをまとめて紹介

CT125・ハンターカブの走行距離が1万キロを超えて、そろそろスプロケ＆チェーン交換したくなってきたのよ。で、せっかくだから純正428サイズから420サイズにチェーンコンバートしてみるよ。こないだハブダンパー交換したら走りはかなり良くなったけど、チェーンコンバートでさらに走りを快適にしちゃおうというワケ。

www-autoby-jp.translate.goog

 

[MyersJ2]

On the JTSprockets website , sprockets section they show light-weight sprockets [scroll down] made of C45 steel . I'm not talking about going to aluminum. I'm wondering if the light-weight just has more metal removed from the design?
With the Trail 125 producing a mere 8+hp every little thing will help it perform better. I'm at 5,214' elevation.

JT Sprockets: Sprockets

I remember seeing those too. I never had much luck finding them easily. I'm guessing they are $$$ too. the first gen bike is I think about 9.2HP converted into SAE HP. The performance increase would be very negligible. Its not a linear HP increase, but rather an increase related to rotational speed. Bascially the faster the rear sprocket turns the more the difference it makes. If you were doing 100mph it'd be considerably more than the realistic 50mph. It is not a 1/1 ration, its like the increasing curve of a bell curve. I think the square maybe? At any rate, you are welcome to give it a shot, but other than being pretty the difference is pretty small.

 

[SLO]

Are the liteweight rear JT Sprockets available for the Honda Trail?

I've messaged JT twice and not received a reply.
Any help please !! ?? ..

I put a 13 tooth on the front. you cannot achieve the RPM necessary without it. 20 w -50 oil ,change it every couple hundred miles until 1000 miles and every 1000 or less after. All the wear occurs in the first 30 miles when new. Exhaust is stupid restrictive. Open intake,and put a 150 injector,and buy extra plugs,go hotter, NGK 6. 238 cam will make a big difference if you don't want to BBK it. YUMINASHI USA. If it weren't for other vehicles, that is what I would be riding.2021 model.

 

[MyersJ2]

I put a 13 tooth on the front. you cannot achieve the RPM necessary without it. 20 w -50 oil ,change it every couple hundred miles until 1000 miles and every 1000 or less after. All the wear occurs in the first 30 miles when new. Exhaust is stupid restrictive. Open intake,and put a 150 injector,and buy extra plugs,go hotter, NGK 6. 238 cam will make a big difference if you don't want to BBK it. YUMINASHI USA. If it weren't for other vehicles, that is what I would be riding.2021 model.

So you buy buy a fuel efficient bike for four grand and you want to spend hundreds if not thousands of dollars to make it go slightly faster. It's a whole lot cheaper to buy a brand new KTM five Enduro 390r which is 44 horsepower for $5,500. Now. Spending all that money on your mini bike to then destroy its gas. Mileage makes no sense

 

[SLO]

I put a 13 tooth on the front. you cannot achieve the RPM necessary without it. 20 w -50 oil ,change it every couple hundred miles until 1000 miles and every 1000 or less after. All the wear occurs in the first 30 miles when new. Exhaust is stupid restrictive. Open intake,and put a 150 injector,and buy extra plugs,go hotter, NGK 6. 238 cam will make a big difference if you don't want to BBK it. YUMINASHI USA. If it weren't for other vehicles, that is what I would be riding.2021 model.

Put a magnetic oil drain plug in it,and you can see when it is broken in. No more metal,and will collect the stuff that you want to remove. The manual is part of the marketing strategy, SALES! SLO. I got a lot from MC SC, but I started thinking.

 

[SLO]

So you buy buy a fuel efficient bike for four grand and you want to spend hundreds if not thousands of dollars to make it go slightly faster. It's a whole lot cheaper to buy a brand new KTM five Enduro 390r which is 44 horsepower for $5,500. Now. Spending all that money on your mini bike to then destroy its gas. Mileage makes no sense

I spent a lot more on my KTM 390 to make it what it is,but it still needs more rise on the bars. The education I received is what is the most important thing. The student excelled the teacher,and the teacher became angry.I had no riding skill,60 years old,major spine reconstruction,and wrecked the trail 125 on the first day,and was not even on it. Broke mirror putting in shed. Nothing is difficult,just different.It is about the roads that I ride. Look at a map,the offer still stands. HUMBLE you will be!

 

[ol mike]

I put a 13 tooth on the front. you cannot achieve the RPM necessary without it. 20 w -50 oil ,change it every couple hundred miles until 1000 miles and every 1000 or less after. All the wear occurs in the first 30 miles when new. Exhaust is stupid restrictive. Open intake,and put a 150 injector,and buy extra plugs,go hotter, NGK 6. 238 cam will make a big difference if you don't want to BBK it. YUMINASHI USA. If it weren't for other vehicles, that is what I would be riding.2021 model.

I have no desire to modify my 23' , I use it for exploring and scouting mostly. Had it two years this month 485 miles on the odometer. I just want to make it more off-road capable. Just yesterday I started mounting the Shinko 2.75 Golden Boy tires. <--Quite the wrestling match , laf.
Ordered a lightweight 13 tooth counter sprocket & a 42 tooth rear. That should give me some good versatility.along with the factory gearing.

I have a 3.00 Shinko waiting in the wings.