FYI: Fitting a Tubus Tara to a Miyata 615gt
#1
FYI: Fitting a Tubus Tara to a Miyata 615gt
In case anybody else decides to try this for themselves, I thought I'd provide my own experience here. With pictures!
The final angle is great, or "optimal" in the words of the very terse Tubus installation instructions. The top bar is almost perfectly level with the ground when installed using the uppermost mounting hole on the fender eyelet of the fork, exactly as pictured in the instructions.
As the OLN distance on my bike is something like 110mm, the provided spacers had to be used. I believe that the mid-fork width is still technically out-of-range even with the spacers, so the top bars had to be "coaxed" into place and so are slightly angled inward.
As for those mid-fork mounting holes! I discovered that they were too large for M5 bolts and assumed that they must be M6. But then I found that M5 bolts slide all the way through the mid-fork mounting holes easily. So I went to the hardware store and after a lot of time digging through drawers of bolts came home with: 40mm M5 bolts, various M6 bolts and a file, and some Loctite blue. I wanted to cover all the bases.
It turns out that the mid-fork mounting holes do NOT fit M6 (good thing I didn't file out the Tara before checking...) Upon closer inspection, it looks like maybe there aren't actually threads at all inside the Miyata's mid-fork mounting points. In any case, M5 passes through them and I had calculated ahead of time that I would need 40mm in order to accommodate the spacer, washers, and a nylock nut.
And of course, since I had to re-mount the fenders to the holes provided by the Tara, my fender line was messed up. Realigning it caused the sharp ends of the stays to jut out menacingly. I am loathe to trim them further as I plan to possibly remove the Tara when I am not planning on touring. However, the Tara is so light (all things considered) that it might make more sense to just leave them on, especially considering that nylock nuts are single-use -- something which the installation instructions alerted me to and which I did not know.
Anyway, that's everything worth mentioning about this project. Perhaps anybody else has had experience with these Miyata 615/1000 mid-fork mounting points? Did I miss something about these? Do they fit M6 with a different pitch than I tried? Or were they always designed with a compression fitting in mind? Am I at risk of the whole thing exploding under load because of the slightly angled in parts?
The final angle is great, or "optimal" in the words of the very terse Tubus installation instructions. The top bar is almost perfectly level with the ground when installed using the uppermost mounting hole on the fender eyelet of the fork, exactly as pictured in the instructions.
As the OLN distance on my bike is something like 110mm, the provided spacers had to be used. I believe that the mid-fork width is still technically out-of-range even with the spacers, so the top bars had to be "coaxed" into place and so are slightly angled inward.
As for those mid-fork mounting holes! I discovered that they were too large for M5 bolts and assumed that they must be M6. But then I found that M5 bolts slide all the way through the mid-fork mounting holes easily. So I went to the hardware store and after a lot of time digging through drawers of bolts came home with: 40mm M5 bolts, various M6 bolts and a file, and some Loctite blue. I wanted to cover all the bases.
It turns out that the mid-fork mounting holes do NOT fit M6 (good thing I didn't file out the Tara before checking...) Upon closer inspection, it looks like maybe there aren't actually threads at all inside the Miyata's mid-fork mounting points. In any case, M5 passes through them and I had calculated ahead of time that I would need 40mm in order to accommodate the spacer, washers, and a nylock nut.
And of course, since I had to re-mount the fenders to the holes provided by the Tara, my fender line was messed up. Realigning it caused the sharp ends of the stays to jut out menacingly. I am loathe to trim them further as I plan to possibly remove the Tara when I am not planning on touring. However, the Tara is so light (all things considered) that it might make more sense to just leave them on, especially considering that nylock nuts are single-use -- something which the installation instructions alerted me to and which I did not know.
Anyway, that's everything worth mentioning about this project. Perhaps anybody else has had experience with these Miyata 615/1000 mid-fork mounting points? Did I miss something about these? Do they fit M6 with a different pitch than I tried? Or were they always designed with a compression fitting in mind? Am I at risk of the whole thing exploding under load because of the slightly angled in parts?
Last edited by zygomorph; 06-11-21 at 08:07 AM.
#2
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I encountered something similar this week. I tried to mount a Surly Front Rack to my 1990 Miyata 1000LT with the provided brackets and M5 bolts. When trying to mount the rack, the M5 bolts weren't catching on the mounting holes. I thought I stripped the mid-fork mounts. I eventually realized, with the help of Brockton Cyclery in Toronto, that the fork mounts are sized for M6's. Unfortunately, the brackets provided by Surly aren't wide enough to accommodate M6 bolts, so the shop used longer M5's and screwed a nut on the other end of the hole.
#3
Senior Member
I recently replaced my Tubus Tara with the Tubus Grand Expedition. I had to use The Tubus Extension Adapter because the mid fork holes on the fork were near an inch higher than the rack mount. The rack is not setup for panniers with bungee hooks. So I used SS hose clamps with handlebar tape for padding.
I had previously purchased new rack stays and they had to be fitted to the rack.
I had previously purchased new rack stays and they had to be fitted to the rack.
Last edited by Rick; 05-17-24 at 02:07 PM.
#4
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The heavier duty Thorn touring bikes are the only ones I am familiar with that use M6. Everybody else seems to use M5. If anyone else uses M6, that will be a surprise to me unless it is a really heavy duty one like a Tout Terrain. I have two Thorns, one is more normal weight for touring, it uses M5 but the really heavy duty Thorn uses M6.
Decades ago, some mid-fork mountings were not threaded. So, no surprise here.
I have heard that Nylock nuts are single use, but I have been re-using them for years and will continue to do that. I am not saying you are wrong, but in my opinion sometimes manufacturers get a bit too stringent with their instructions.
Decades ago, some mid-fork mountings were not threaded. So, no surprise here.
I have heard that Nylock nuts are single use, but I have been re-using them for years and will continue to do that. I am not saying you are wrong, but in my opinion sometimes manufacturers get a bit too stringent with their instructions.
#5
Senior Member
The heavier duty Thorn touring bikes are the only ones I am familiar with that use M6. Everybody else seems to use M5. If anyone else uses M6, that will be a surprise to me unless it is a really heavy duty one like a Tout Terrain. I have two Thorns, one is more normal weight for touring, it uses M5 but the really heavy duty Thorn uses M6.
Decades ago, some mid-fork mountings were not threaded. So, no surprise here.
I have heard that Nylock nuts are single use, but I have been re-using them for years and will continue to do that. I am not saying you are wrong, but in my opinion sometimes manufacturers get a bit too stringent with their instructions.
Decades ago, some mid-fork mountings were not threaded. So, no surprise here.
I have heard that Nylock nuts are single use, but I have been re-using them for years and will continue to do that. I am not saying you are wrong, but in my opinion sometimes manufacturers get a bit too stringent with their instructions.
I've also taken the fender off and on when putting on fork cages, so have taken off and put fender back on at least five times, so 2x each time removing and retightening. I do tighten it well but don't go all gorilla on it.
This is just supporting a top of fender though, if your rack bolts have a lot of play in the hole, perhaps thickening them up a bit would be good?
Just an idea and maybe not a good one-- I always figure reducing movement is always good.
#6
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#7
Senior Member
sorry, wrote that quickly.
I meant if the bolt was really loose going in, maybe thicken it up with some tape or something so that it doesnt rock back and forth in the hole. Maybe just tightening the nut properly is ok, but I was imagining if the hole was way too big for the bolt.
or maybe I'm completely off base with that.
oh--how much does your lighter skinned Grunnam weigh again? I weighed my fathers 17ft and it was 73lbs. I havent weighed mine in eons, cant recall its weight.
I meant if the bolt was really loose going in, maybe thicken it up with some tape or something so that it doesnt rock back and forth in the hole. Maybe just tightening the nut properly is ok, but I was imagining if the hole was way too big for the bolt.
or maybe I'm completely off base with that.
oh--how much does your lighter skinned Grunnam weigh again? I weighed my fathers 17ft and it was 73lbs. I havent weighed mine in eons, cant recall its weight.
#8
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sorry, wrote that quickly.
I meant if the bolt was really loose going in, maybe thicken it up with some tape or something so that it doesnt rock back and forth in the hole. Maybe just tightening the nut properly is ok, but I was imagining if the hole was way too big for the bolt.
or maybe I'm completely off base with that.
oh--how much does your lighter skinned Grunnam weigh again? I weighed my fathers 17ft and it was 73lbs. I havent weighed mine in eons, cant recall its weight.
I meant if the bolt was really loose going in, maybe thicken it up with some tape or something so that it doesnt rock back and forth in the hole. Maybe just tightening the nut properly is ok, but I was imagining if the hole was way too big for the bolt.
or maybe I'm completely off base with that.
oh--how much does your lighter skinned Grunnam weigh again? I weighed my fathers 17ft and it was 73lbs. I havent weighed mine in eons, cant recall its weight.
The 17 standard I think was rated at 75 pounds, lightweight 17 at 60. Later they came out with a "super" that I think was roughly mid way between the lightweight and standard with a different stiffer alloy that was more susceptible to cracking.
Not sure about the weights on the shoe keel model.
#9
Senior Member
My 18 lightweight Grumman was rated at 66 pounds if my memory is correct. I think it is a 1976 model. Portage yoke (Grumman of course) adds a few pounds. The 18 foot, the lightweight has 9 ribs, the standard has 5. I think the 17 standard has 3 ribs and the lightweight has 7, but memory cells are getting old on this kind of data.
The 17 standard I think was rated at 75 pounds, lightweight 17 at 60. Later they came out with a "super" that I think was roughly mid way between the lightweight and standard with a different stiffer alloy that was more susceptible to cracking.
Not sure about the weights on the shoe keel model.
The 17 standard I think was rated at 75 pounds, lightweight 17 at 60. Later they came out with a "super" that I think was roughly mid way between the lightweight and standard with a different stiffer alloy that was more susceptible to cracking.
Not sure about the weights on the shoe keel model.
It's bonkers how light some boats are now, although I'm sure one has to be careful with them.
#10
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I apologize in advance for being off topic again.
My kevlar solo canoe, Wenonah Prism is 30 something pounds. They now list it as 30 even but I think mine was a few more pounds.
https://wenonah.com/Canoes.aspx?id=121
The small blue backpack in the photo is my food pack, I put that up in the bow and can shift that fore and aft for balancing the boat when I load it. As I eat food day after day, I transfer more weight to that pack for balancing the boat. I carry that blue pack and the canoe at the same time. I bought the yellow backpack after I got the canoe, my other waterproof pack was too wide to fit in between the gunwales behind the seat.
Two clevis pins are used to attach the portage yoke (a few more pounds) to the boat, easy to attach and remove. I made the portage yoke pads decades ago for a different boat, the yoke is an old wood one from an Old Town brand canoe. The hardware with clevis pins came as a kit to make your own portage yoke for a solo canoe.
I prefer a kayak paddle in a solo canoe. But it drips a lot of water into the boat, I use the high rubber boots to keep my feet dry as the paddle drips onto the boots instead of dripping onto my socks. And at portages I like to load and unload the boat in the water, those boots work well for that.
My kevlar solo canoe, Wenonah Prism is 30 something pounds. They now list it as 30 even but I think mine was a few more pounds.
https://wenonah.com/Canoes.aspx?id=121
The small blue backpack in the photo is my food pack, I put that up in the bow and can shift that fore and aft for balancing the boat when I load it. As I eat food day after day, I transfer more weight to that pack for balancing the boat. I carry that blue pack and the canoe at the same time. I bought the yellow backpack after I got the canoe, my other waterproof pack was too wide to fit in between the gunwales behind the seat.
Two clevis pins are used to attach the portage yoke (a few more pounds) to the boat, easy to attach and remove. I made the portage yoke pads decades ago for a different boat, the yoke is an old wood one from an Old Town brand canoe. The hardware with clevis pins came as a kit to make your own portage yoke for a solo canoe.
I prefer a kayak paddle in a solo canoe. But it drips a lot of water into the boat, I use the high rubber boots to keep my feet dry as the paddle drips onto the boots instead of dripping onto my socks. And at portages I like to load and unload the boat in the water, those boots work well for that.
#11
Senior Member
You said it, my fault though!
That must be pretty cool paddling something that light, and I can see how you'd notice the weight balance more. Is it turny wurny in winds because so light or does it track fairly well?
And ya, drips would be annoying, and yes, unloading it in water seems the best way to be nice to the hull.
Very cool setup.
To others, this is like talking about riding a UCI weight limit road bike! Fast and responsive.
That must be pretty cool paddling something that light, and I can see how you'd notice the weight balance more. Is it turny wurny in winds because so light or does it track fairly well?
And ya, drips would be annoying, and yes, unloading it in water seems the best way to be nice to the hull.
Very cool setup.
To others, this is like talking about riding a UCI weight limit road bike! Fast and responsive.
#12
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You said it, my fault though!
That must be pretty cool paddling something that light, and I can see how you'd notice the weight balance more. Is it turny wurny in winds because so light or does it track fairly well?
And ya, drips would be annoying, and yes, unloading it in water seems the best way to be nice to the hull.
Very cool setup.
To others, this is like talking about riding a UCI weight limit road bike! Fast and responsive.
That must be pretty cool paddling something that light, and I can see how you'd notice the weight balance more. Is it turny wurny in winds because so light or does it track fairly well?
And ya, drips would be annoying, and yes, unloading it in water seems the best way to be nice to the hull.
Very cool setup.
To others, this is like talking about riding a UCI weight limit road bike! Fast and responsive.
The light weight of the boat in the wind is hardly noticed compared to a heavier boat because when I weigh about 185 pounds, roughly 60 pounds of gear and food, a boat that is 30 some pounds versus a boat that is 50 or 60 pounds is not much different when you consider that it is total weight that you are displacing in the water. It is like loading all my camping gear on my titanium touring bike, yeah the titanium might have cut a pound or two off of total weight compared to steel, but that small of a weight reduction is essentially round off error.
A canoe paddle does not work very well if you are sitting in the middle of the boat for steering unless you keep switching sides. But a kayak paddle is invented by someone sitting in the center of a long skinny boat, that is what it was designed for. I am not sure why some people in solo canoes use a canoe paddle instead of a kayak paddle. But you need a longer kayak paddle in a canoe and not many kayak paddles are made that are long enough for that. My spare is a canoe paddle, that is more for narrow streams than for lake travel.
The big difference is that I can carry the canoe and a heavy food pack at the same time across a long portage. Then go back for my second pack, the paddles and PFD in the second crossing. That would be a lot tougher with a heavier boat.
I have only used the solo canoe on three canoe trips so far, so still getting used to what kinds of wind are safe and what is less so.
I catch a lot less wind when I am in my kayak because it does not extend very high above the water line in comparison. I can easily travel on windy days in rough water in a kayak but the canoe is best used on smaller lakes where you have a lot less fetch. When you think about it, kayaks were invented by people that could not swim to use for ocean travel, but canoes were invented by people that could swim to use on streams and lakes with less wind and waves.
Landing the boat and unloading it solo can be tough if there is bad footing or if you have high waves. With two people, one can hold the boat while the other unloads. But with one person, all that one person can do is unload the boat without holding on to it. The blue pack in the photo below was my anchor keeping the boat from floating away when I was not holding onto the boat, there is a small line (green) to the canoe from the pack.
I am not posting any more off topic on this thread, sorry to those that are bothered by that.