GSX1400 Owners .org

Technically Speaking => Chains & Sprockets => Topic started by: Jeykey on Monday, 09 May 2022, 01:57 AM

Title: Rear sprocket torque
Post by: Jeykey on Monday, 09 May 2022, 01:57 AM
So how much are the rear sprocket nuts torque ? 102 Nm, chapter 6-32 or 60 Nm chapter 2-25. I did 102 upon installation.
Title: Re: Rear sprocket torque
Post by: KiwiCol on Monday, 09 May 2022, 03:11 AM
102Nm is written on the Torque Spec sheet download.  I have the pages printed off & laminated, they live in the garage near where I need them.  Laminating them stops them getting dirty & tatty.
Title: Re: Rear sprocket torque
Post by: Hooli on Monday, 09 May 2022, 06:13 AM
Two point one four eleven six clicks of the elbow...

I never torque them, I tighten them up with a dash of threadlock & they've never given me an issue.
Title: Re: Rear sprocket torque
Post by: SpongeBob on Monday, 09 May 2022, 07:05 PM
It's 102Nm as stated in several places in the workshop manual, including the summary torques table near the end of the workshop manual. The 60Nm that is shown on page 2-25 seems to be a typo and this appears to be the value for the GSXR sprocket nuts, which are smaller in diameter and with less threads.
Here in the picture you can see a GSXR sprocket/carrier/nut, and a GSX nut next to it as a comparison.
Title: Re: Rear sprocket torque
Post by: Mick_J on Monday, 09 May 2022, 07:25 PM
Are you sure the 102Nm is not a typo, seems very high for a sprocket, more like an axle value.
Title: Re: Rear sprocket torque
Post by: grog on Monday, 09 May 2022, 07:26 PM
As Hooli said, thats been me. I do have a new tension wrench, prob use it next time.
Title: Re: Rear sprocket torque
Post by: Eric GSX1400K3 on Monday, 09 May 2022, 08:14 PM
I use 100Nm on the rear axle nut via a torque wrench.  102Nm for the sprocket carries nuts is too high. 60Nm sounds right without checking the manual.
Title: Re: Rear sprocket torque
Post by: SpongeBob on Tuesday, 10 May 2022, 01:34 AM
102 Nm would then be a "typo" repeated several times over the workshop manual, especially in the detailed parts of the book, while 60Nm is only quoted once in the general service chapter near the beginning.
Also, there has been a lengthy discussion on FB a year or two ago about that, and at the end the OP got an official reply from Suzuki in UK confirming the 102Nm value.

As I said, the difference in values between GSXR sprocket nuts and GSX one makes sense, as both studs/nuts diameter (M12 vs M10 if I remember correctly) AND the greater number of threads in the GSX case make the latter accept more tightening torque -- this has been confirmed to me by a mechanical engineer working in the tooling manufacturing business.

As a practical example: on MVAgusta bikes, the rear wheel nut is somewhere around 45mm+ ID, with very fine thread pitch and quite a lot of threads; and even being made of Ergal it is to be tightened at.. 220 to 240Nm! I can tell you you need quite a large torque wrench for that :-)
Title: Re: Rear sprocket torque
Post by: Jeykey on Tuesday, 10 May 2022, 03:12 AM
OK @SpongeBob thanks for the reply. I think the UK Suzuki reply puts an end to the discussion.
Title: Re: Rear sprocket torque
Post by: seth on Tuesday, 10 May 2022, 03:50 AM
Only thing to add is that all torque setting are for new nuts and bolts if your reusing old ones the torque should be lowered as the bolts are already partially stretched .
I'm with @Hooli I just get them tight with a wee drop of thread lock on them .
Reusing old bolts/studs with torque wrenches is how most get snapped.
:cheers: