[iswoolley]

Need to replace the chain and sprockets on my Y-reg XR400. I want to slightly undergear from standard, and I believe that the standard is 15-45 tooth sprockets with a 108 link, 520 profile chain.

Should I go smaller on the front, say to a 14-45 (1:3.21) combination? Or should I go larger on the back, say to a 15-48 (1:3.20) combination? Both about the same gearing, but what are the pros and cons to changing the front/rear sprocket?

Iain

 

[haich]

I've got standard gearing on mine, and it suits me and the type of terrain we ride.
Not sure I'd want to lower the gearing, and lose a little top end, as we ride quite a bit of tarmac between lanes.
If you read the Gordon's mod page, he has lowered his front sprocket a tooth to 14t
If you do go with a larger rear sprocket, don't forget you'll need a longer chain.........

 

[jasonbc]

Need to replace the chain and sprockets on my Y-reg XR400. I want to slightly undergear from standard, and I believe that the standard is 15-45 tooth sprockets with a 108 link, 520 profile chain.

Should I go smaller on the front, say to a 14-45 (1:3.21) combination? Or should I go larger on the back, say to a 15-48 (1:3.20) combination? Both about the same gearing, but what are the pros and cons to changing the front/rear sprocket?

Iain

I ran mine maily with 1 tooth less at the front made offroading a bit easier just gave it a bit less top end but better pulling power. I have a genuine honda xr400rt manual for sale if your interested honda part number 62kcy00c

1 tooth at the front equates to 3 at the back by rule of thumb

 

[phil w]

Best thing with front sprocket on XRs is you can change them in minutes. keep the 45 rear and carry a 13 an 14 in your bumbag and change to suit. I always used a 43 rear with front combos and if the ride home was along one then a 16 front would go on. Brilliant bike for changing the gearing on, if the riding was very tight an hilly would use 13 but I found that a 14 would manage most off road stuff

 

[AIRWOLF]

small front sprockets wear quicker.

 

[jasonbc]

small front sprockets wear quicker.

Shouldn't make much difference if chain lubrication and tension are checked and corrected, also wear rate is irrelevant if the desired gearing is what you need. A few quid for a sprocket ain't worth worrying about and lets face it most of us have spares lying around

 

[iswoolley]

Best thing with front sprocket on XRs is you can change them in minutes.

That's the kind of info I was after. :thumbup: Thanks! Looks like I'll go for a 48 at the back, and a 14, 15, 16 at the front, to be used as required.

Iain

 

[phil w]

Only issue with the 16 is I used it on roads home because the case saver didnt fit with it although some say grinding it down a bit allows this.... but then if you've ground it down it may not save the case!!

 

[Oakframer]

For woods riding I tried 14-47 but decided, after trial and error that 15 -47 worked well for me.

 

[Rubberman52]

hi , i am just about to buy a new chain for my xr4, you say that with standard gearing it has 108 links, i don't have a chain splitter so i am going to ask the shop to take some off for me and just want to be sure it is 108. I am getting a 520 did with 120 links many thanks guys, rub

 

[jasonbc]

You don't need a chain splitter to remove links on a chain use either a dremmel or angle grinder to take the heads off the pins then a pin puch to drive the pin out will do, it's how i always do them

 

[Rubberman52]

You don't need a chain splitter to remove links on a chain use either a dremmel or angle grinder to take the heads off the pins then a pin puch to drive the pin out will do, it's how i always do them

sounds interesting, what size pin punch do you need ? Do i just hit the pin with a hammer and the pin punch? sorry never done it before,

cheers buddy

 

[jasonbc]

what size pin punch do you need ? Do i just hit the pin with a hammer and the pin punch? sorry never done it before,

cheers buddy

The pin punch needs to be slightly smaller than the pin or it won't go through ther hole. Or you can gring the 2 pin heads off then tap the side plate off with either a screwdriver or chisel. 2 minute job

 

[Rubberman52]

ah i see now, spot on

cheers