[ryanwhalen]

So I've been meaning to swap off my road-rashed crash bars for a while. I finally got around to taking out the wrenches today to remove the old ones. As I hunkered down over the first bolt and gave it a good turn I noticed it seemed very tight. I did the old mental lefty-loosey-righty-tighty imaging and had a look at the bolt to be sure I was turning the right way (I was). Unfortunately as I inspected the bolt I saw that while my wrenching didn't loosen the bolt it did break a decent chunk of engine housing.

So, my questions:

• Has this happened to anyone else?
  
• Is there a relatively easy fix? (I'm an apartment dwelling roadside mechanic)
  
• What would you do in my situation?

I've attached a photo of the damage.


IMG_20120518_165054 by Ryan Whalen, on Flickr

[Timothy_d]

Wellllllll. . .

You're kind of screwed, kind of not.

You may be able to get someone to aluminum weld it, but it will never be the same.
That all being said, you have only lost one of the 8 engine mounts.

If it was me, I'd keep riding it, periodically checking the upper mount for cracking.

Pretty much makes your engine guard useless though.

[murrayf]

dont feel bad i am sorry to say that the stress that broke that is probably the same impact that put the road rash on the crash bar

that mounting point is not meant to take side load when the bike fell on the crash bar it was weakened and may have even cracked then

you loosening the bolt just finished it

that having been said on the inside of that boss is plenty of room if you find someone who can tig or heliarc aluminum there is lots of room

to repair that so it can be as strong that is the only mount that has a ton of room behind it i have welded them successfully before

then run a fine tig bead on the front for looks a little grinding and sanding and your good

BTW dont try to tkae the bolt out find someone to weld it have them weld the part with the rad out then when its hot and strong from them welding it

the bolt will come out very easy

[FADM Stern GNSF]

Well, no need to panic at this time. I would first get the bars off to make sure you dont have issues with the other 3 front mounts. If they are OK then as stated earlier, its only 1 of 8 and it may be savable.

Once the bars are off (hopefully the other 3 are ok) check to see how much farther the tread goes into the block past the broken section. Based on the Pic you may actually have enough to do the job. You really need a minimum of 1/2 of thread left over, if its more then that is even better. The trick may be getting the bar and broken bit out as chances are some of the threaed postion is in the broken section making it hard to remove from the bolt. You will probabaly need to put the broken bit in a vise and soak it with a form of penitrating oil and get the bolt out.

Now, if you have at least 1/2" of thread left in the block, you wont need to have the broken bit welded on, but it will have to go back as a "spacer" if you want to use new bars. So, lets say you have the 1/2" thread left in the block, here is the best and cheapest way to fix it. Take the broken bit and drill out the threads so the bolt will pass straight through it (you dont want any threads in this bit, just a clean hole the bolt can pass through without "pulling" on it. Now, clean the bit and block well, and glue it back on with JBWELD. You can hand tighten a bolt in to hold it in place while the JBWELD sets.

Now, if you dont have 1/2" minimum of threads, based on this pic you can tap the threads deeper provising the hole doesnt bottom out. If it does you can carefully drill the hole deeper BUT ONLY AS FAR AS WHERE THE SECTION MEETS THE BLOCK. If you look at the pic, it looks like you have approx 3/4" of mounting tab BEFORE it joins to the "meat" of the block. Drilling deeper could compromize a passage, so use a drill stop to prevent this. You can then tap out the hole and your good to go.

You may want to check the hole depth (use a piece of wire) even if you have 1/2" thread, as it will give you an idea of where the hole bottoms out in relationship to the block. Threading a bolt in until it stops will tell you how deep the threads go (most threaded holes will be deeper than the threads are). You may choose to tap a little deeper to get more threaded area.

I will not keep my fingers crossed for you that the other 3 come off without damage (use penitrating oil/rust buster stuff before just to help) and that you have a lot of thread still left. Remember you may need to get a bolt a fraction longer (most bolts only go in to the first half of a threaded hole to make sure the bolt never bottoms out.)

[ryanwhalen]

Thanks for the advice all. I've blasted the bolts with some penetrating oil and will try to remove the crash bars after they sit for a while. I'm worried about the bar on the other side, as that's the side the bike went down on (and thus that's the mount point that actually suffered the worst blow). Luckily each bar only attaches to the engine at one point (or perhaps unluckily, maybe this leads to too much stress on that one point). The other bolts are below the bike on a frame that is bolted on.

Once the bolts are off I'll reassess. If there's enough thread left I might just try a JB weld as per FADM's suggestion.

[ryanwhalen]

The rest of the unit disassembled with no problems. I've replaced the nut on the right side (the non-broken side). The bolt on the broken side doesn't reach the non-broken portion of the mount. I reckon there's between 1/2 and 1/4 of an inch of thread left (the break is diagonal), but I'll need a longer bolt just to be able to reach any thread at all.

So the general feeling is that I could tap a little further into that hole? I'm willing to try so as to give myself a little more thread to hold onto. I've never tapped anything before, but it can't be that hard. Can it?

[FADM Stern GNSF]

Well, first you need to see how much deeper the hole goes (will probabaly go deeper than the threads). Most taps will only tap down about 1/4"-1/2" of usable thread before the tap bottoms out (unless you get a special tap that is flat on the bottom and doesnt have its teeth taper at the end, called a bottom tap). If the hole only goes in a little, you can drill it deeper, but only until you get down near the block area. Since the broken part is probabaly also threaded and the bolt wont go much past the break (if at all) you would definatly need a longer bolt.
The fact the break is "green beeen cut" wont really matter once the broken section is drilled and glued into place, as it will act as a guide to keep the bolt running true. It will though be a bit tricky getting the tap to start properly, but as long as you are carfull to keep it straight, it will follow in the existing threads until it starts cutting deeper. When taping turn about 1 turn in when cutting, then back it out 1/2 - 1 full turn to break the swarf, and use cutting oil to keep the aluminum from binding with the steel cutting teeth.

[Allan]

ryanwhalen, on 18 May 2012 - 10:22 PM, said:

The rest of the unit disassembled with no problems. I've replaced the nut on the right side (the non-broken side). The bolt on the broken side doesn't reach the non-broken portion of the mount. I reckon there's between 1/2 and 1/4 of an inch of thread left (the break is diagonal), but I'll need a longer bolt just to be able to reach any thread at all.

So the general feeling is that I could tap a little further into that hole? I'm willing to try so as to give myself a little more thread to hold onto. I've never tapped anything before, but it can't be that hard. Can it?

Not sure if I would drill much further into the hole, You may be able to but you don't want to go into the water jacket or something.



I have been driving this one for about 3 years now with no problem. I took the crash bars off of my bikes,,I would rather replace a head than a block.

Here is another thread about this.


And another similar one

In this one they are saying you can change the head,,but your mount is not in the head.

[FADM Stern GNSF]

Agree, but Im not sure how far the hole goes in, I do know it CAN be drilled in as far as the point that meets verticle area under the head. The hole may be that deep already, but if not that point would be the max limit. Also, the hole may go deeper that the threads, and even a few more threads cut in would be even better.

Once he gets the bars off and can meassure whats there (how deep the threads go but hand threading in a bolt, and how deep the hole is by using a piece of wire) its hard to tell for sure the best aproach. From the pics he could probabaly use whats there, but best to get the meassurements before making a call.

[Allan]

There is a pic in the first thread I linked to,,in that pic it looks like you could drill in another quarter inch or so. If you measure it you could probably drill it a bit.

[FADM Stern GNSF]

Yea, thats a good pic of it. Seems like that pic has a break closer to the block and still has a lot of threads left. He may actually be alright with what he has.

Ryanwhalen, once you get the bar off can you post a pic of what threads are left in the hole, as it would give us a way better bit of info to see if you need to do anything (other than a longer bolt)

BTW, when you get a longer bolt be carefull to make sure you size it so it goes in as much as possible WITHOUT bottoming out. This is important so you dont put stress on the threads left and still be able to make the bolt (and bar) tight. May need to get a bolt larger and grind a bit off the end

[murrayf]

that lower engine boss on that side of the block tapers and gets thinner as it gets closer to the block

i dont think there is enough meat to drill much deeper it is a big bolt and the wall of the boss gets a lot thinner

even though it looks like its built up for the bolt its just a tapered continuation

of the shape it not the same thickness

[TonyR]

I tend to lean on the paranoid side and thee is a welding shop here in acworth, ga that I bet can weld that for less than $100.
I can tell you what MY choice would be.
I hate throwing $100 at a service I think I should just learn for myself but they have equipment and experience that I do not have time or $$ to acquire.
I would rather have all them in place. It was designed that way for a reason and Honda tends to have good designs.

Your mileage may vary and I am not saying anyone else is wrong. They have more knowledge than I do about this kind of thing. I am simply saying if I could afford the $$ I would spend the $$ to have it welded.

[Allan]

TonyR, on 20 May 2012 - 11:51 PM, said:

I would rather have all them in place. It was designed that way for a reason and Honda tends to have good designs.

My engine only falls off the bike a couple of times a year,,I just coast to a stop,,then go back and get it and bolt it back in place,,I do carry spare bolts though.