Clunk in rear

[martinh]

I got little over 1000 miles on the clock now and have noticed when I put the bike in 1st and let out the clutch the rear will clunk. I never had a shaft drive before so I don't know if this is normal. I had the oil changed at the dealer at 600 miles and planning to do another change of all fluids. The clunck comes when I let out the clutch slow and put it back in. It seems like the gears are a little loose. Any one else hear this?

 

[tomatocity]

Did they change the Final Drive gear oil?

 

[~TABASCO~]

I would check the oil and the level. There is lash in a drive shaft on the ring and pinion. If its loud or noticeable its probably not right.....

 

[roy]

Mine does it with 2100 miles on it and I am not worried. Normal not a problem. Listen to a BMW and when it starts sounding like that then worry ) seriously I believe it is just the way it works. I changed my oil at 600 miles with Yamalube gear oil, stock oil came out in pretty good shape with no residue on the nut.

 

[tomatocity]

When filling the final drive fluid (on the centerstand)... slowly turn the rear wheel in reverse (could be wrong about the direction) and it will pull the fluid into the final drive... keep turning the wheel until it is overfull then let it drain a bit.

If you turn the opposite direction it will push the fluid out of the fill hole.

I let the final drive drain overnight while on the sidestand.

 

[Buckeye56]

I think the clunk may be the spring-loaded shock absorber in the shaft drive. The ring and pinion have very little back lash, the service manual talks about adding or removing 0.008 inch thick shims to adjust it. Just looked in the service manual, the torque damper is in the transmission not the drive shaft. But it may not be a bad idea to have it checked.

 

[Tremor38]

I think your are just now noticing a noise that has been there all along. It's normal. I heard it on my very first ride, starting with zero KM on a brand new bike. In didn't think much of, but commented to the dealer anyway. He took a ride on it and confirmed it's the same noise all the FJRs make...normal.

 

[20valves]

::021::

::001::

 

[martinh]

thank you all for the input. I am riding it more and worring less, put on another 200 miles today. I want to change the oil in there again.

 

[20valves]

I want to change the oil in there again.

You have issues!

 

[~TABASCO~]

thank you all for the input. I am riding it more and worring less, put on another 200 miles today. I want to change the oil in there again.

I prolly will to again at 1000... I just threw in some Mobil-1

 

[Tremor38]

I prolly will to again at 1000... I just threw in some Mobil-1

80 weight Mobil- 1? I wasn't aware of such a thing. I didn't know they had gear lube.

 

[tomatocity]

80 weight Mobil- 1? I wasn't aware of such a thing. I didn't know they had gear lube.

http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Fully_Synthetic_Gear_Lube_75W-90LS.aspx

80 is between 75 and 90

edit: or
http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Fully_Synthetic_Gear_Lube_75W-140LS.aspx

What would be the performance difference with 75-90 and 75-140?

 

[Tremor38]

http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Fully_Synthetic_Gear_Lube_75W-90LS.aspx

80 is between 75 and 90

edit: or
http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Fully_Synthetic_Gear_Lube_75W-140LS.aspx

What would be the performance difference with 75-90 and 75-140?

Yeah, what I'm trying to say is that I've always associated sythethic oil with engine oil only. I was completely ignorant that there was gear lube. That also shows you how much I've used sythetic oil for anything I might start with the S10. Never spent his much on bike.

 

[markjenn]

Personally, I'd stick with the 75-90 stuff for the M1 gear lube - I think in this application, you want to be closer to factory spec viscosity. And any oil (gear or engine) which has a wider range of viscosities gets this wider range with viscosity improvers (VIs) which have tradeoffs -they're not as good lubricants as the base stocks. Basically, wider is better for temp extremes, but in this application, good shear-stable lubrication is probably more important.

I think the M1 stuff is very good oil, but the term "synthetic" is so ambiguous these days, it doesn't tell you much. It's a marketing term, not a technical one.

- Mark

 

[tomatocity]

Not questioning anything. I have never used or had the reason to use gear oil for a motorcycle but I am a believer in Mobil 1 synthetic for auto / truck.

Here is the application information for both Mobil 1 gear oils.

75W-90: Applications
•Mobil 1 Synthetic Gear Lubricant LS 75W-90 is SUITABLE for use in modern high performance automobiles like SUV's, Vans and Light duty trucks requiring API GL-5 level performance
•Mobil 1 Synthetic gear Lubricant LS 75W-90 is intended for initial fill, topping-off or refilling differentials, final drives, transfer cases and other gear applications where lubricants meeting API Service GL-5 and multi-purpose or mild EP gear lubricants are recommended
•Not recommended for automatic, manual or semiautomatic transmissions for which engine oil or automatic transmission fluids are recommended
•Where extended service intervals and warranties are required

75W-140: Applications
•Mobil 1 Synthetic Gear Lubricant LS 75W-140 is recommended for use in modern high performance vehicles like sport utility vehicles, vans and light duty trucks requiring API GL-5 performance that require excellent durability
•Mobil 1 Synthetic Gear Lubricant LS 75W-140 is intended for initial fill, topping-off or refilling differentials, final drives, transfer cases and other gear applications where lubricants meeting API Service GL-5 and multi-purpose or mild EP gear lubricants are recommended
•Mobil 1 Synthetic Gear Lubricant LS 75W-140 can also be used in rear axles where API Service GL-4 lubricant is recommended
•Not recommended for automatic, manual or semiautomatic transmissions for which engine oil or automatic transmission fluids are recommended
•Recommended for many limited slip applications. For certain high level LS applications, additional limited slip additive may be required if axle chatter is observed.