[kuc45]

I've seen posts in the past about various loose nuts and bolts that are common on the ZR-7(S) that account for various rattles and buzzes on our bikes.

Last night, I did a quick check of my bike looking for them. I found:

-4 of 8 exhaust nuts were loose with 1 barely more than hand tight.
-2 of 4 of the 6mm axel bolts were a little loose
-3 of 4 of the 4mm fairing bolts were loose in varying degrees

The bike wasn't what I would consider to be noisy before checking, but was noticably quieter riding into work this morning. When you have a few minutes, you might want to go over your bike. I admit that what I found suprised me and I'm going to make a note to add this to my periodic maintenance check list.

Craig

 

[qheuie]

i also checked the exhaust fasteners and 4 of them were loose. i did not get a chance to check the axle bolts, i need to get the right allen and a torque wrench, too..

thanks for the heads up, Craig!

q

 

[Martin64]

Another thing to consider when checking these items (especially the exhaust flange nuts) is that you don't twist the stud off. If you're using a long wrench to tighten them with, it becomes increasingly easier to twist them off because you have more leverage. About every other time I tighten mine, I use the torque wrench just to make sure I'm not going over board.

 

[Tom Bozeman]

Yes Martin, it was your advice some time ago that I ordered the relatively inexpensive torque wrench from Harbor Freight.com that solved my exhaust bolt problems. Thanks again, Man, Tom

 

[Martin64]

Another thing that may be happen is the cap nut may "top-out" on the stud. One of us may end up with tight flange nuts and still get an exhaust leak if the exhaust gaskets flatten out. That may deserve some investigation. :?

 

[Andy]

Regarding the exhaust nuts...

Martin, I think the nuts come loose due to the heating and cooling cycles. I don't think you have worry about "top-out" on the stud.

One option would be to replace the acorn nuts with standard nuts. You would also want to use a lock nut and a washer. It wouldn't look as pretty but then you might not have to worry about loose exhaust nuts.

Another option is to use some Lock-Tight. But that may lock the nut so tight that if you tried to loosen the nut, the stud may back out.

I use a SHORT end-wrench to tighten them. Like Martin said don't use a long end-wrench because you could strip the threads.

Andy

 

[Martin64]

It's a fairly easy thing to check. Just get a nut to fit the studs and a bolt that will fit the cap nuts. If one or the other doesn't fit then it could be that the threads are streatching. But I think you're probably right. But I'm gonna put that on my, "I'm Bored as Hell and I want Something To Do" list.

 

[treestman]

Yes Martin, it was your advice some time ago that I ordered the relatively inexpensive torque wrench from Harbor Freight.com that solved my exhaust bolt problems. Thanks again, Man, Tom

Tom,

Lots of torque wrenches at HarborFreight.com. Did you need more than one? What did you get?

 

[Martin64]

It's the 1/4" drive, in/lb, "break-away" style. It's somewhere around $30-$35.

 

[titomike]

Replace your exhaust header nuts with some nice chrome locknuts. Problem solved.

Yamaha XJR1300 ones fit a treat and will set you back about $2 each ( us $1 each )

 

[qheuie]

so i check my exhaust bolts before EVERY ride now, they always seem to be loose to some degree. what exactly is the torque spec for these bolts? i generally twist them on eith my 3/8 ratchet but it would be pretty nice to set them at the right torque.
eventually i will get the maintenance manual

later,
josh

 

[Martin64]

I use the "Basic Torque for General Fasteners" guide on page 1-10 of the manual.
Thread Diameter Ft/lbs
5mm 30-43 in/lb
6mm 52-69 in/lb
8mm 10-14 ft/lb
10mm 19-25 ft/lb
12mm 33-45 ft/lb
14mm 54-72 ft/lb
16mm 83-115 ft/lb
18mm 125-165 ft/lb
20mm 165-240 ft/lb
The book doesn't have a specific torque for those and I haven't been in the garage all week-end to look at my notes. Just size it up and use good judgement. Make sure they are cold when you do it.

 

[qheuie]

martin, when you say "thread diameter", is that the actual diameter of the bolt? so say i am using a 10mm socket, the bolt is obivously not 10mm, maybe say 7 or 8mm because the head is bigger, right?... just wonderin so i am clear on the torque i set
thanks!
josh

 

[Martin64]

Correct.

You can use a wrench to measure the diameter. Just put the open end portion of the wrench up to the threads. When you find one that's close, that's usually it. Just don't try to jam one on the threads, could screw up the threads.