Engine Mounting Bolts - What Torque ?

[Guest Gas_Up_Lets_Go]

I've had a search but alas I find nothing (if you can find a thread please point me in the direction)...

 

Just fitted some Puig Engine bars, and I'm looking for the torque settings for the front top and bottom engine mounting bolts, the 17mm bolts (thats the nut dimensions)

 

Does anyone have access to this information ?  and care to share it ??

 

Since fitting the bars I've noticed a little more vibration. The old Varadero was a pig if you didn't have the correct torque on the engine mounts, I'm thinking the NC is similar.

 

Anyone ??

[Guest PaD]

I would like to ask about lenght of the engine bolts. As I don't have an answer for the original question you are free to call me a hijacker and throw me out of this thread.

Speaking about thread - here is my question-

Aren't the original engine bolts a little bit too short when you add crash bars and mount them to the engine mounts? I know SW Motech supplies longer bolts with their crash bars but I've heard the Givi ( and Puig?) don't.  I think it's a rather fine thread into aluminium in the engine and applying high torque with less thread ( with the bars attached) could maybe damaged the thread?

I'm not an engineer so I really don't know if this should be a concern.

[Guest dentonlad]

I've had a search but alas I find nothing (if you can find a thread please point me in the direction)...

 

Just fitted some Puig Engine bars, and I'm looking for the torque settings for the front top and bottom engine mounting bolts, the 17mm bolts (thats the nut dimensions)

 

Does anyone have access to this information ?  and care to share it ??

 

Since fitting the bars I've noticed a little more vibration. The old Varadero was a pig if you didn't have the correct torque on the engine mounts, I'm thinking the NC is similar.

 

Anyone ??

54 Nm

[Guest Gas_Up_Lets_Go]

54 Nm

 

 

Blimey, that much less than I estimated it.

 

Thanks very much.

 

Bolt length - I recall that there was plenty of thread inserted, and the flang on the bars is only a couple of mm, but it's worth a check anyway - cheers

[embee 7,288]

As a general guide, the engagement length into light alloy should be at least 2xD , so for example with an M8x1.25 fastener it should be at least 16mm, M6=12mm, M10=20mm etc..

[Griff 1,556]

I would like to ask about lenght of the engine bolts. As I don't have an answer for the original question you are free to call me a hijacker and throw me out of this thread.

Speaking about thread - here is my question-

Aren't the original engine bolts a little bit too short when you add crash bars and mount them to the engine mounts? I know SW Motech supplies longer bolts with their crash bars but I've heard the Givi ( and Puig?) don't.  I think it's a rather fine thread into aluminium in the engine and applying high torque with less thread ( with the bars attached) could maybe damaged the thread?

I'm not an engineer so I really don't know if this should be a concern.

 

That was a question also raised by an esteemed member of the international forum. He did a thread on the subject and also decided on the length of the replacement bolts required for Givi Bars. Getting the new bolts was not easy though.  Have a search on there to see if you can find the thread.

[Guest PaD]

Thank you embee and Griff for answering my off topic question.

[Guest outlaw]

Found on a different site.

is the information I used that Beemerphile posted in a thread back in August, 2012 and which I followed to the letter in mounting my Givi bars to my dct bike. I did order the my addtional bolts from the local Fastenal store.

Quoting from Lee's thread on this subject:

"In this case, I think the engine guard and the mounting points are fine, but I disagree strongly with re-using the stock engine bolts. So, I plan to install longer bolts to achieve NO LESS than the original amount of thread engagement as it represents the best that we can do. All four of the threaded attachment points are open to the inside, so a bolt longer than necessary will do no harm so long as there is sufficient length of thread to get to where the threaded portion starts. I will install somewhat longer than necessary bolts so that I have some reserve in case I add a later accessory, such as a skidplate, that wants to mount to the same place.

Here are the numbers for the engine bolts on the US spec 700x with manual transmission (not DCT). All are grade 10.9 M12-1.25 hex washer head bolts.

UPPER LEFT: 35mm long bolt with 7mm from face of frame flange to start of thread
UPPER RIGHT: 45mm long bolt with 17mm from face of frame flange to start of thread
LOWER LEFT: 80mm long bolt with 46mm from face of frame flange to start of thread
LOWER RIGHT: 55mm long bolt with 30mm from face of frame flange to start of thread

The stock bolts are not exactly flush with the exit of the bosses, so the numbers above don't clarify that the thickness of the threaded bosses are between 25 and 27mm thick. I don't want to reduce it by 20% and add potential impact forces. I publish them here so that you don't have to do the research. In order to keep the engine in position, you have to remove, measure, and reinstall them one at a time. Since they are open on the inside I plan to get bolts 10mm longer so long as the distance to start of thread is adequate. I could not find these bolts in washer head, but +10mm will allow enough length to add a washer under the head. The upper right bolt can be re-used on the upper left. I purchased three new bolts in 55mm, 70mm (65 was not available), and 90mm length with grade 10.9 washers from:

Bolt Depot - Nuts and Bolts, Screws and Fasteners online"

Another quote from Beemerphile on torque:

"The Givi instructions are simple pictures with little technical information. The NC700X service manual from Honda specifies 54 N-m for the 12mm engine mounting bolts. Since they are extra fine threads into aluminum, make sure that the threads are clean (internally and externally) and approach the torque slowly. I normally do it in about three steps."

I followed Lee's instructions and did not have any problem installing the guards.
 

[Guest outlaw]

I have not yet put on my engine bars

[Griff 1,556]

Found on a different site.

is the information I used that Beemerphile posted in a thread back in August, 2012 and which I followed to the letter in mounting my Givi bars to my dct bike. I did order the my addtional bolts from the local Fastenal store.

Quoting from Lee's thread on this subject:

"In this case, I think the engine guard and the mounting points are fine, but I disagree strongly with re-using the stock engine bolts. So, I plan to install longer bolts to achieve NO LESS than the original amount of thread engagement as it represents the best that we can do. All four of the threaded attachment points are open to the inside, so a bolt longer than necessary will do no harm so long as there is sufficient length of thread to get to where the threaded portion starts. I will install somewhat longer than necessary bolts so that I have some reserve in case I add a later accessory, such as a skidplate, that wants to mount to the same place.

Here are the numbers for the engine bolts on the US spec 700x with manual transmission (not DCT). All are grade 10.9 M12-1.25 hex washer head bolts.

UPPER LEFT: 35mm long bolt with 7mm from face of frame flange to start of thread

UPPER RIGHT: 45mm long bolt with 17mm from face of frame flange to start of thread

LOWER LEFT: 80mm long bolt with 46mm from face of frame flange to start of thread

LOWER RIGHT: 55mm long bolt with 30mm from face of frame flange to start of thread

The stock bolts are not exactly flush with the exit of the bosses, so the numbers above don't clarify that the thickness of the threaded bosses are between 25 and 27mm thick. I don't want to reduce it by 20% and add potential impact forces. I publish them here so that you don't have to do the research. In order to keep the engine in position, you have to remove, measure, and reinstall them one at a time. Since they are open on the inside I plan to get bolts 10mm longer so long as the distance to start of thread is adequate. I could not find these bolts in washer head, but +10mm will allow enough length to add a washer under the head. The upper right bolt can be re-used on the upper left. I purchased three new bolts in 55mm, 70mm (65 was not available), and 90mm length with grade 10.9 washers from:

Bolt Depot - Nuts and Bolts, Screws and Fasteners online"

Another quote from Beemerphile on torque:

"The Givi instructions are simple pictures with little technical information. The NC700X service manual from Honda specifies 54 N-m for the 12mm engine mounting bolts. Since they are extra fine threads into aluminum, make sure that the threads are clean (internally and externally) and approach the torque slowly. I normally do it in about three steps."

I followed Lee's instructions and did not have any problem installing the guards.

 

 

 Yep, that is the one I was thinking of.