Need riser bolts! Please someone help!!!

Nice! I was on the partzilla website and used the st1300 PA model link since the police models came with risers installed as factory. The factory non-riser bolts are too short, hence why I need the longer bolts with the threaded centers. I have the other 2 bolts in the longer length already. BUT, if you can make me some, that would be awesome and save me some money! If it becomes more of a chore than you expected, let me know. Ill order through partzilla. I would be extremely grateful if you had the skill and parts to recreate these parts. I’ll be eagerly standing by.
 
Partzilla! Thank you. I think I will order from there. Good suggestion since Genmar was not responding to me. Appreciate all the responses and info!
Make sure you are looking at ST1300PA. That has the longer bolt, look at your bike and the P to see the difference on the fiche.
 
If you just need a bolt drilled and tapped, anyone with even just a mini-lathe would be able to do this size for you. A million and one uses for such a wonderful machine tool, and good to have a friend like STRider who can knock it out for you.
I think I'd do it in stainless being up in the PNW, though. I've had good luck with this outfit for fasteners not locally available: https://www.boltdepot.com/Default.aspx
 
Per the parts list, that bolt is 8x18.
The factory non-riser bolts are too short, hence why I need the longer bolts with the threaded centers.
You need the 8mm X 43mm flange bolt that I posted in post # 3 above.
It is Honda P/N 90137-MCS-A30. This is the bolt for the police spec riser.

The Honda bolts are $10.00 each. By the time that you purchase two corrosion resistant bolts and two corrosion resistant washers, I don't think that the amount that you will be saving will be worth your time and trouble of finding, drilling and tapping them.

If you already have some suitable 8mm bolts and washers that will provide 43mm of thread starting from the washer, the head of the bolts will need to be drilled and tapped for a 4mm screw 7mm long. 43mm is the length of the Honda bolt. You may be able to use longer bolts as well if that is what you have, but check for clearance.

I would just order them from Honda and be done with it. You can temporarily use any 8mm bolt until the correct ones arrive. The only difference is that you won't be able to put the cover on for a few days until you get the new bolts.
 
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If this was a machinist forum, we'd expect to see a shot of the work in the lathe. Just sayin'.
 
I've checked multiple on line sources and none have either the civilian or police spec bolts in stock.

Stainless would be great, but those I had ready access to were zinc plated. Stainless is also harder to drill and tap.

This took me literally twenty minutes to finish.

Plus, the rise of the police and GenMar risers are different based on what's reported on their site. See my previous posts.
 
I knew there'd be photos! I never miss an opportunity.

Student lathe showing the cutting tool got too close to the chuck more than once..
 
Or this...

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SHOW OFF!!
Easy when you have all the equipment free-of-charge at your whim isn't it? I wish I had a lathe, and a milling machine wouldn't hurt either.

That should be exactly what he needs, with two spares to boot, good on you.

The only thing that I would suggest is that when these are being installed, check to make sure that the bolt shank is not longer than the combined thickness of the handle bar and riser. The reason that I suggest this is because it has been reported on this forum that Gen-Mar makes the riser for the police ST1300, and whether it came from Honda or Gen Mar they are one in the same part. If that is the case, the 43mm length bolt specified by Honda should be the correct length. I would check to make sure that the extra 17mm is not causing the bolt shanks to bottom out against the bridge causing them to tighten up before sufficient clamping force of the three parts has been achieved. I have no idea what the distribution of the extra 17mm is, but 17mm is a significant difference in length if a significant amount of it went in to the shank. Good news is that it is an easy fix- just thread the bolt a little more if needed.
 
SHOW OFF!!
Easy when you have all the equipment free-of-charge at your whim isn't it? I wish I had a lathe, and a milling machine wouldn't hurt either.

That should be exactly what he needs, with two spares to boot, good on you.

The only thing that I would suggest is that when these are being installed, check to make sure that the bolt shank is not longer than the combined thickness of the handle bar and riser. The reason that I suggest this is because it has been reported on this forum that Gen-Mar makes the riser for the police ST1300, and whether it came from Honda or Gen Mar they are one in the same part. If that is the case, the 43mm length bolt specified by Honda should be the correct length. I would check to make sure that the extra 17mm is not causing the bolt shanks to bottom out against the bridge causing them to tighten up before sufficient clamping force of the three parts has been achieved. I have no idea what the distribution of the extra 17mm is, but 17mm is a significant difference in length if a significant amount of it went in to the shank. Good news is that it is an easy fix- just thread the bolt a little more if needed.

Andrew, thanks for all the input and support on my effort to help @dlim

I recall other posts that noted that the PA spec risers were made by GenMar for Honda. I made my length decision based on that 1Cruiser website that said "the risers ... raise the bars up 32mm". As I said before 18 + 32 = 50mm, but I defer to those with more first hand experience. :wave1: (<-- intended to be just one guy bowing in honor, but our emojis don't include that one.)

And my free bolt supply didn't include 50mm ones, only 60mm... so it's easier to shorten a bolt that's too long than to add length to one that's too short!

So, everything you said to David is valid. I see three paths forward for him if they're too long as delivered (which I think they will be).
1. If there's sufficient thread available, simply cut the excess from each bolt, dress the threads at the end and call it good.
2. Same as 1. but if the threads don't go up the shank far enough, cut more with an M8 die as you suggested before cutting.
3. Add ~17mm worth of washers, or better yet a spacer, under the head of the bolt to ensure the clamping that this bolt is there to deliver. This would result in the cover being raised 17mm higher than it would have been otherwise, but that wouldn't be too terrible.

Then again, I could return to the shop and use a parting tool to make one set 43mm long. Yesterday was convenient because it was during our weekly robotics meeting anyway.
 
Hopefully this doesn't make me look foolish, but how would I go about cutting the bolts shorter without unnecessarily damaging the threading? Would a simple hacksaw work? I've never had to shorten a threaded bolt like this before and don't want to damage the excellent work you've done.

I agree and believe the correct length is 43mm. Although 17mm isn't much, I think it will probably bottom out before properly securing the bar down.
 
I only pretend to be a machinist on weekends so take this FWIW, but I have doubts about cutting more threads on these bolts. My understanding is the threads are probably rolled, so you can't just cut more and maintain the integrity of the fastener. That's even if the shank diameter is large enough to support the required size to cut the threads. If these were going to hold a top box to a rack, sure, no worries. But handlebars? And the zinc coating will be gone from the new threads meaning potential rust. I don't mean to be a downer, but if these bolts are too long, I'd humbly suggest buying the right size and starting over as opposed to adding threads.

For the OP, cutting them shorter isn't an issue as long as you have enough thread engagement. I have no idea what that amounts to, but I'd personally want to engage with every female thread available.
 
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I only pretend to be a machinist on weekends so take this FWIW, but I have doubts about cutting more threads on these bolts. My understanding is the threads are probably rolled, so you can't just cut more and maintain the integrity of the fastener. That's even if the shank diameter is large enough to support the required size to cut the threads. If these were going to hold a top box to a rack, sure, no worries. But handlebars? And the zinc coating will be gone from the new threads meaning potential rust. I don't mean to be a downer, but if these bolts are too long, I'd humbly suggest buying the right size and starting over as opposed to adding threads.

For the OP, cutting them shorter isn't an issue as long as you have enough thread engagement. I have no idea what that amounts to, but I'd personally want to engage with every female thread available.
Absolutely correct on every count @Smudgemo

However in the absence of authentic OEM or accessory producer's versions of these fasteners, I'm confident these will serve very well. I wouldn't hesitate for a moment to use them on my bike. Yes, there is risk of corrosion from the removal of the zinc coating but there are ways to mitigate that - anti-seize, a touch of spray paint... all viable options. Each of these is only one of three M8 bolts that hold each of the handle bars in place so I think the structural risk is low too.

I offer to David how he plans to make use of these.

That said, @dlim , you could use a hacksaw to cut the bolts, but a much better technique - which I'll use when I get home from work - would be to use a Dremel with a cutoff wheel. To minimize the risk to the remaining threads and keep the cut square I'll double nut the bolt with the threads to be removed extending out and cut them off with the Dremel. I'll then dress edge with the cutoff wheel. If necessary, I have a thread repair kit I can use to dress them properly.
 
I think if the threads marry well and there is sufficient contact, I think it’ll hold ok fine. Especially with the support of the other 2 bolts properly torqued down. Dremel is a great idea by the way. I look forward to seeing these and I appreciate the work and effort.
 
Andrew, thanks for all the input and support on my effort to help @dlim

I recall other posts that noted that the PA spec risers were made by GenMar for Honda. I made my length decision based on that 1Cruiser website that said "the risers ... raise the bars up 32mm". As I said before 18 + 32 = 50mm,
If the police spec risers sold by Honda are indeed made by Genmar and are the same as the ones that Genmar sells under their own name, 43mm screws should be correct. My reasoning for this is that the length of the civilian ST1300 screws in this location are 18mm in length. The police spec screws for this same location are 43mm. If they are the same riser, they should use the same length screw.

Unfortunately, I don't have a Genmar riser to measure how much extra length it adds at these specific screw locations, as opposed to its nominal thickness. David has it in hand, so he should be able to measure it and let you know.

Good luck. Report back what length you end up with for curiosity sake.
 
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Here are some pictures with a ruler I had on-hand. Does this help at all? The 2 bolts in the image are the correct length for the risers. I’m just missing the 3rd bolt with the threaded center.
 
The riser is adding about one inch, which is 25 mm. That matches Honda's literature. Honda specified that a bolt that is 25mm longer is required, so that also matches up. Once washers are added to the bolts in your picture, they would measure 43mm from the underside of the washer, the same length that the Honda flange bolts are. Everything indicates that 43mm bolts are correct.

Tom made four bolts for you. You might consider asking him to machine two of them to 43mm as measured from the underside of the washer. Make sure that there is also 25mm of available thread remaining- I am basing this on the thread length of the bolts in your picture that you wrote are the correct bolts. Leave the other two as is so you can shorten them to whatever length you need if a plan B is required.
 
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