Help RS125 NF4

[husaberg]

I have been driving myself nuts searching the Web for the dimensions for the spline of a RS125 Honda.
Does Anyone Know or have one they could measure.
I am trying to find a suitable sprocket to match these dimensions but only in 415 or 420.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg

The closest i can find in a suitable size is this but it will need some careful hacking.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf546.jpg

[Yow Ling]

I have been driving myself nuts searching the Web for the dimensions for the spline of a RS125 Honda.
Does Anyone Know or have one they could measure.
I am trying to find a suitable sprocket to match these dimensions but only in 415 or 420.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg

The closest i can find in a suitable size is this but it will need some careful hacking.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf546.jpg

The spline is the same as cr125 and rg150,

[husaberg]

The spline is the same as cr125 and rg150,

Thanks for your reaponse but i am now even more confused.
So are you saying the RS125 NS4 is the same spline as a RG150 (which i can't get the measurements for I do see Rg125 though) and an early 80's Cr125? Which seemed to change nearly every year according to a catalogue.

[Yow Ling]

Are you saying the RS125 NS4 is the same spline as a RG150?
yes plus 7 char

[RDjase]

I have been driving myself nuts searching the Web for the dimensions for the spline of a RS125 Honda.
Does Anyone Know or have one they could measure.
I am trying to find a suitable sprocket to match these dimensions but only in 415 or 420.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg

The closest i can find in a suitable size is this but it will need some careful hacking.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf546.jpg

Just measured a JT548 off the KR150 (same as RG and FXR, 428 chain) it the same spline size as JT546.
A RS sprocket fits on the KR150 shaft but the RS125 is 18mm at the inside of the spline not 16mm like the JT548,

JT wont fit on the RS shaft, RS sprocket held on by a 8mm cap screw and concave washer, KR sprockets use the splined plate with two 6mm cap screws (like Honda XL and XR, think they are the same size as well)

Lucky I have a KR150 sitting in my front room and a RS engine awaiting its frame to return next week:yes:

[RDjase]

Lucky I have a KR150 sitting in my front room and a RS engine awaiting its frame to return next week:yes:

Front room = Winter workshop :yes: not :cold:

[husaberg]

Just measured a JT548 off the KR150 (same as RG and FXR, 428 chain) it the same spline size as JT546.
A RS sprocket fits on the KR150 shaft but the RS125 is 18mm at the inside of the spline not 16mm like the JT548,

JT wont fit on the RS shaft, RS sprocket held on by a 8mm cap screw and concave washer, KR sprockets use the splined plate with two 6mm cap screws (like Honda XL and XR, think they are the same size as well)

Lucky I have a KR150 sitting in my front room and a RS engine awaiting its frame to return next week:yes:

Thanks for that so whilst not ideal i might get away with the RS sprocket on a NSR125 spline then i will have to retain the sprocket for which there is no holes for the XL/XR style retainers. I have previously and successfully done this before with circlips.

Plus a bit of filing as well to get the splines out to 5mm

[quallman1234]

Just measured a JT548 off the KR150 (same as RG and FXR, 428 chain) it the same spline size as JT546.
A RS sprocket fits on the KR150 shaft but the RS125 is 18mm at the inside of the spline not 16mm like the JT548,

JT wont fit on the RS shaft, RS sprocket held on by a 8mm cap screw and concave washer, KR sprockets use the splined plate with two 6mm cap screws (like Honda XL and XR, think they are the same size as well)

Lucky I have a KR150 sitting in my front room and a RS engine awaiting its frame to return next week:yes:

Are the NX4 and NF4 splines both the same?

What are you getting done to NX4 frame?

[RDjase]

Thanks for that so whilst not ideal i might get away with the RS sprocket on a NSR125 spline then i will have to retain the sprocket for which there is no holes for the XL/XR style retainers. I have previously and successfully fone this before with cirlips.

I used two circlips (were thinner than the groove so used two) to hold a 16 tooth front on the KR at a gearing change at HD Tri Series as a temparary fix till I got a 2 hole sprocket, was still on there after the South Island Nats, PMCC and Taupo Nats final with no problems

[husaberg]

I used two circlips (were thinner than the groove so used two) to hold a 16 tooth front on the KR at a gearing change at HD Tri Series as a temparary fix till I got a 2 hole sprocket, was still on there after the South Island Nats, PMCC and Taupo Nats final with no problems

Bodging is great and factory.
The KTM50's which have a half round hole too rather than a spline. Only have a circlip too.
http://t1.gstatic.com/images?q=tbn:ANd9GcQrt_XKoCoUkVrbN_S0edN_w8qSn-Z5nTfCCzjoMCkuoIZMw9of

[quallman1234]

Circlip should be fine, my KDX200 has a circlip holding the front sprocket on.

[Bert]

I'm sure one of us will have one or ten (NF or NX). Sort out something tomorrow.

What actual pitch are you after? 415, 420 or 428?

I had a few issues with my TZR spline (found that a YZ80 fitted 428 though) then the boys surface ground it down to 415 for me.... but I was told not to come back...

[husaberg]

I'm sure one of us will have one or ten (NF or NX). Sort out something tomorrow.

What actual pitch are you after? 415, 420 or 428?

I had a few issues with my TZR spline (found that a YZ80 fitted 428 though) then the boys surface ground it down to 415 for me.... but I was told not to come back...

Wanting to fit a 415 as preference (as i have a number of 415 sprockets)
I could live with 420. but not 520 which is STD.

This is the STD NSR125 Front Sprocket
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg


Are you sure you machined a 428 to 415 and not 420 to 415?
I thought the rollers or bushes were different diameter (as below) even though the pitch is the same?

[RDjase]

Are the NX4 and NF4 splines both the same?

What are you getting done to NX4 frame?

Nothing much, Just replacing the rivnuts that hold the coil on as the bolt that holds the earth wire/coil fell out at Manfeild last month, DNF ;-(
Been getting the KR's ready for sale so left the RS at work so I had some room. One KR sold today :yes:

[Bert]

Are you sure you machined a 428 to 415 and not 420 to 415?
I thought the rollers or bushes were different diameter (as below) even though the pitch is the same?

you could be right there; can't be assed walking out to the shed to look at the box that it came in.:cold::cold:

[husaberg]

you could be right there; can't be assed walking out to the shed to look at the box that it came in.:cold::cold:

Fair enough i hear the winters are tough up North.

[Bert]

Fair enough i hear the winters are tough up North.

yea mate (1 degree is just too cold for this white boy) inside by the fire is where its at; esp when motogp is on....

[cotswold]

I have been driving myself nuts searching the Web for the dimensions for the spline of a RS125 Honda.
Does Anyone Know or have one they could measure.
I am trying to find a suitable sprocket to match these dimensions but only in 415 or 420.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg

The closest i can find in a suitable size is this but it will need some careful hacking.
http://www.jtsprockets.com/fileadmin/code/images/small/jtf546.jpg

I know you won't get anything in 415 as i have spent 6 months looking for the exact same size ( gp125 )
There are a number of chinese pit bike sprockets that are the right size but in 420, Red Dot a company in the UK sell them on E Bay. There is also an option of getting some made by a company in the States and if you fancy going in that direction let me know as i may be keen on splitting the cost (depending on how high the cost) http://www.rebelgears.com/sprockets.html

[jasonu]

Thanks for your reaponse but i am now even more confused.
So are you saying the RS125 NS4 is the same spline as an early 80's Cr125? .

Why be surprised, the NF4 is a CR bottom end.


Wanting to fit a 415 as preference (as i have a number of 415 sprockets) still at my house...
I could live with 420. but not 520 which is STD.


Are you sure you machined a 428 to 415 and not 420 to 415?
I thought the rollers or bushes were different diameter (as below) even though the pitch is the same?
I have several of both and never had an issue.




I know you won't get anything in 415 as i have spent 6 months looking for the exact same size ( gp125 )
There are a number of chinese pit bike sprockets that are the right size but in 420, Red Dot a company in the UK sell them on E Bay. There is also an option of getting some made by a company in the States and if you fancy going in that direction let me know as i may be keen on splitting the cost (depending on how high the cost) http://www.rebelgears.com/sprockets.html

Don't do that. Simply buy some cheap as chips 420's with the correct spline and get them surface ground.




Plus a bit of filing as well to get the splines out to 5mm

Good luck with that mate, they are as hard as fuck.

[husaberg]

Why be surprised, the NF4 is a CR bottom end.

because the splines on the cr changed spline nearly every year.

I have several of both and never had an issue.

428-415?



Don't do that. Simply buy some cheap as chips 420's with the correct spline and get them surface ground.



Good luck with that mate, they are as hard as fuck.
I have filed and ground them before after annealing them so am i:cold:
And yeah thanks for running the northern hemishere sprocket storage operation Jason;)

[jasonu]

I have filed and ground them before after annealing them so am i:cold:
And yeah thanks for running the northern hemishere sprocket storage operation Jason;)

I have had both 420 and 428 ground to 5mm thick which makes them the same as 415.
I remember someone posting here that 428 are different somehow but I have not had any problem using them.

[F5 Dave]

Would have been me as they are different, the rollers are different sizes. On a rear sprocket that will mean that you can't run a 428 vs 420. On a front you can probably get away with it but it is much kinder to run a 420 & 420 sizes are usually available for most things, unless you have a particularly queer Honda (my MB is only slightly ghey & MB50 sprockets fit).

Think 4.8mm is a bit more clearance. Don't forget to add the bevel on the teeth, I've seen people try to run flat sided sprockets, the munters:pinch:. You can imagine what happens, or tries to happen.

[jasonu]

Would have been me as they are different, the rollers are different sizes. On a rear sprocket that will mean that you can't run a 428 vs 420. On a front you can probably get away with it but it is much kinder to run a 420 & 420 sizes are usually available for most things, unless you have a particularly queer Honda (my MB is only slightly ghey & MB50 sprockets fit).

Think 4.8mm is a bit more clearance. Don't forget to add the bevel on the teeth, I've seen people try to run flat sided sprockets, the munters:pinch:. You can imagine what happens, or tries to happen.

IIRC the 428 rollers are wider than the 420 but still have the same pitch so if you are grinding them thinner to suit the 415 chain (same pitch as 420) then it doesn't matter.

[F5 Dave]

I think the rollers are a larger diameter so same pitch yes, but require a larger scollop in the sprocket. or run other way around may have some more slop.

[quallman1234]

Nothing much, Just replacing the rivnuts that hold the coil on as the bolt that holds the earth wire/coil fell out at Manfeild last month, DNF ;-(
Been getting the KR's ready for sale so left the RS at work so I had some room. One KR sold today :yes:

Oh yeap! I had the exact same thing replaced during nationals.

See you at round 3!

[cotswold]

IIRC the 428 rollers are wider than the 420 but still have the same pitch so if you are grinding them thinner to suit the 415 chain (same pitch as 420) then it doesn't matter.

Um this is what I found with a 428 chain and a 415 sprocket, it may have caused a few issues?

[jasonu]

Um this is what I found with a 428 chain and a 415 sprocket, it may have caused a few issues?

Lucky for me I was using 415 chain on 415 rear sprockets and a mixture of 420 and 428 ground down front sprockets. I will be sure to have another look before my next race meeting...:sweatdrop

[husaberg]

Would have been me as they are different, the rollers are different sizes. On a rear sprocket that will mean that you can't run a 428 vs 420. On a front you can probably get away with it but it is much kinder to run a 420 & 420 sizes are usually available for most things, unless you have a particularly queer Honda (my MB is only slightly ghey & MB50 sprockets fit).

Think 4.8mm is a bit more clearance. Don't forget to add the bevel on the teeth, I've seen people try to run flat sided sprockets, the munters:pinch:. You can imagine what happens, or tries to happen.


I have had both 420 and 428 ground to 5mm thick which makes them the same as 415.
I remember someone posting here that 428 are different somehow but I have not had any problem using them.


Lucky for me I was using 415 chain on 415 rear sprockets and a mixture of 420 and 428 ground down front sprockets. I will be sure to have another look before my next race meeting...:sweatdrop

Or could have been me too Dave;)
i posted the roller sizes vs width a page back.

Wanting to fit a 415 as preference (as i have a number of 415 sprockets)
I could live with 420. but not 520 which is STD.

This is the STD NSR125 Front Sprocket
http://www.jtsprockets.com/fileadmin/code/images/small/jtf327.jpg


Are you sure you machined a 428 to 415 and not 420 to 415?
I thought the rollers or bushes were different diameter (as below) even though the pitch is the same?
I am not sure how much difference the roller size makes to the tooth profile though but the sprockets are different to look at even accounting for the width.
The reason i checked was when i was going to send you the spare KX85 ones and i couldn't figure out why they looked 420 size but the 420 chain would wrap around them.

[husaberg]

OKay this is what i have found out i think there was some confusion with my two pics that i missed......

RS125 Hondas sprokets are the same spline as a RG125 FXR150 and GP125 so anyone wanting to do a 415 conversion buy these.
AS confirmed by Diesel pig (thanks Neil)

If you have a Honda NSR125 well you will have to modify something to work......bugger

[Bert]

OKay this is what i have found out i think there was some confusion with my two pics that i missed......

RS125 Hondas sprokets are the same spline as a RG125 FXR150 and GP125 so anyone wanting to do a 415 conversion buy these.
AS confirmed by Diesel pig (thanks Neil)

If you have a Honda NSR125 well you will have to modify something to work......bugger

Yip had the same issue with the TZR but found the mx 85 splines met the requirements (and a bit of time on the surface grinder)...

So is the cr85 the same???

[husaberg]

Yip had the same issue with the TZR but found the mx 85 splines met the requirements (and a bit of time on the surface grinder)...

So is the cr85 the same???

NO the early ones are the same as a MB the later ones cr80/85 are a multi spline. The RS was my last hope.
i have been through heaps of catalogs (you know what i am like, anorak wise) i can only maybe hope the Chinese did one the same but they normally stick to old style spines that are common. JT do a 428 conversion but my heart is in a 415 as i have some RS srockets.
Honda has betrayed me.lol

[Bert]

NO the early ones are the same as a MB the later ones cr80/85 are a multi spline. The RS was my last hope.
i have been through heaps of catalogs (you know what i am like, anorak wise) i can only maybe hope the Chinese did one the same but they normally stick to old style spines that are common. JT do a 428 conversion but my heart is in a 415 as i have some RS srockets.
Honda has betrayed me.lol

Ass well your only real hope is to find a 420 blank (or very small spline) and someone with a spark eroder or wire cutter..... Or cut the core spline out of a 520 and weld it back into a 415...

[steveyb]

Water cutter goes through sprockets no worries.
I use The Water Cutting Company in Wellington to cut KTM spline into RS125 415 front sprockets for the IMD250.
Just supply an example of the spline you need and let them model it up and cut the RS sprockets you have.
You will just need to spend a bit of time with file on the exit side of the water cut as it does not cut perfectly parallel.

[Kickaha]

Fabrum in Chch do waterjet cutting, if you have someone who can do a dxf file it'll cost you even less as there wont be a set up fee, there used to be a guy in Prebbleton who did wire cutting to

[husaberg]

Water cutter goes through sprockets no worries.
I use The Water Cutting Company in Wellington to cut KTM spline into RS125 415 front sprockets for the IMD250.
Just supply an example of the spline you need and let them model it up and cut the RS sprockets you have.
You will just need to spend a bit of time with file on the exit side of the water cut as it does not cut perfectly parallel.


Fabrum in Chch do waterjet cutting, if you have someone who can do a dxf file it'll cost you even less as there wont be a set up fee, there used to be a guy in Prebbleton who did wire cutting to

That's some bloody useful information. Who can do a DXF file?

[Grumph]

That's some bloody useful information. Who can do a DXF file?

Fabrum can do the lot - but be warned, it's much cheaper to do the machine and weld option as discussed.
One of the partners in Fabrum is Hugh Reynolds who you should remember.

[Bert]

That's some bloody useful information. Who can do a DXF file?

ZCAD or A9Cad (my preferred) are free and can produce dxf. simple to use.

then google a chain/sprocket example (scale to the correct pitch); add spline and done.

[husaberg]

Fabrum can do the lot - but be warned, it's much cheaper to do the machine and weld option as discussed.
One of the partners in Fabrum is Hugh Reynolds who you should remember.


ZCAD or A9Cad (my preferred) are free and can produce dxf. simple to use.

then google a chain/sprocket example (scale to the correct pitch); add spline and done.

thanks ..both But Hugh doesn't sound familar.....

[mr bucketracer]

will look for a spocket today guessing you want somthing around a 420 ? dad bought all of whites sprockets , so we have shit loads

[mr bucketracer]

check fxr150 site hucky

[husaberg]

OK this is the NX4 1995 vs 1994 NF4 Chassis measurements.

[Yow Ling]

OK this is the NX4 1995 vs 1994 NF4 Chassis measurements.
306108
the drawing says NX5 isnt that a 250 ?

[husaberg]

the drawing says NX5 isnt that a 250 ?

Its a typo (my own) and I deleted the original publisher file too, I think lol
I will fix it when I can be arsed recreating it........I was arsed about 8 minutes later

[husaberg]

340746340747340748
looks like there might be an earlier version of the NSR spocket spline that might even be a direct fit. With the elusize RS125 dimensions

[husaberg]

NSR125R and CRM125 415 sprocket.
349354
https://mmgracingstore.com/en/front-sprocket/8980-5166-front-sprocket-honda-nsr-125-crm-125-415-pitch-mj-corse.html#/118-front_sprocket-15

this is the RS125 dimensions.
349353

[husaberg]

Not NF4 but NX4

i seen tjhis this morning
https://www.trademe.co.nz/a/motors/motorbikes/parts-for-sale/other/listing/4161605084

so a bit of backwards search shows this
353222
then this
353223353225
then this
353224
just to be sure

wrong thread where was the one where we were talking about RS125 nf4 steering head bearings