I just picked up a new Miyata saddle at the British Uni Convention yesterday and immediately set to work converting it to an air saddle. However Miyata seem to have redesigned the fixings and have changed their work practices making stripping a new saddle almost impossible.
At first I noticed that they’ve stopped using washers and are now using a different design of nut with a round flange at the base to take the place of the washer. Taking the first one off was very hard but I figured it was just stiff. After it came off I looked at the base of the nut and it had a serrated surface similar to the bottom surface on a crank nut. Looking at the saddle where the nut had been the surface was deeply scored and the nut appeared to have been put on with a lot of force. I then noticed that the thread surface of the bolt was covered in white thread paste.
After the first nut the second and third nut wouldn’t come off at all. They just spun in their holes. This seemed odd as on my previous saddle these two nuts were attached to single U shaped bolt and so should not be able to turn.
As I intended to replace the cover with a gemcrest cover, I decided on drastic action and cut away the original and ripped away the padding. Big problems, the U-shaped double ended bolts are no more and they’ve all been replaced by the standard bolt round topped bolts. As the plastic base is too soft, four of the bolts were just spinning in their holes and wouldn’t come undone.
When I got home today I set about trying to finish the job. To remove the stuck bolts and cut two flats on either side of the rounded bolt head. Then used a set of mole grips to grasp the flats and hold the bolt still while I tried to undo the nuts. The nuts were very stiff but they did eventually come off. Looking at some of the holes, the nut had been put in with such excessive force that it had melted into the saddle base by several millimetres.
What I think has happened is that in order to save money and simplify stock control, Miyata have done away with the U bolts, acorn nuts and washers and have replaced them with standard bolts and the new nut shape in every hole. Possibly as a consequence of this they have had to start using thread paste to ensure the nuts don’t come loose. The thread paste has made assembly difficult so they have started using power tools to get the nuts on. Power tools and soft plastic don’t mix so I ended up with four bolts that wouldn’t come undone a base plate that is next to useless and a cover in several pieces. The only redeeming feature is that I’d intended to replace the cover with a gemcrest and the base plate with one of Rogers Carbon fibre ones. But this still leaves me with several useless bolts and no immediate idea of how I’m going to get everything back together again.
So the moral of this story is - if the nuts on your Miyata saddle have the new style flanged nut and no washer, think long and hard before deciding to take it to bits. It’s now an awful lot harder to do now than lot used to be.
And if anyone from Miyata reads this - please stop using thread paste and power tools. You’ve damaged a near perfect design. Please go back to the old style.
Thanx for that post Noel. I bought a miyata seat too at BUC9 (I’m the kid who asked to have a go on your nimbus, had a go and then rudely ran off to buy a seat… Thanx for letting me have a go anyway mate )
Any way, fortunately i have’nt messed with it, although i did try to lightly tighten the bolts holding the front bumper, and noticed that one of them just kept spinning quite easily. I thought it could be a stripped thread or the head of the bolt not being attatched properly. You have confirmed my fears. I too am going to think twice now about an airseat conversion.
Roger, do you have any smart ideas about how best to do an air conversion with the new dodgy bolts? Is it possible to buy the u shaped bolts elsewhere?
Thanks for the warning, Noel. I assume that the shipments of new seats to the UK and the US have the same “upgrades”. I was planning on doing the same conversion to one that I recently bought in the states. Has anyone else had this problem with the new seats?
Yeah, ditto what Harper said. Now I’m starting to have seccond thoughts about my planned airseat conversion. Let me know if there are any ways to make the conversion easier, while still keeping the damage to all the components at a minimum.
If this is true and all miyata seats are like this, is there a better seat? I am in need of a seat right now and I was planning on getting a miyata and doing the airseat conversion on it. Are the seats good even without doing the conversion? And if not what seat should I get?
I just checked, and my nuts are also sunken about a couple of mm into the base. I didnt try to takethem off, but i was able to see and feel that the bottom bit of the nut was flat with the plastic from the handle. Drummond, is it possible to just import the base and handles seperate from the seat? This really is upsetting.
My mother told me to lay off the sailor talk, but I must say it- Dang nabit!
Greg Cohen is also in the midst of making a new type of Muni, and from what he tells me, there is definately some seat or seat handle work improvement, although, i dont think the seat is going to be available separately. He might just sell the handle separately. Hmm… maybe he said that the seat is a normal seat, but has a his handle on it. Anyway, I guess we will just wait and see.
Oh dear. Have they also changed the plastic mold for the seat base? The holes for the U-shaped bolts are round rather than square. The square head carriage bolts will not work correctly in a round hole. I would hope that they would be using a new seat base mold with square holes. If they are, in fact, using the carriage bolts in the round holes then the situation is not good at all.
I was on the phone this morning for a few minutes with Mark at Uniycle.com. It was for an unrelated matter, but I got the impression that they know about the problem(not sure, though). Mark builds the air seat conversions. Perhaps call him and ask if he has any tricks for getting around the problems with the new seats.
This really sounds bad. What’s John D. going to do with(what could be) nearly 1500 obsolete Miyata saddles when the (above mentioned) seats come out? At least he can use them in starter kits and not recommend them for air seat conversion.
Hey, John Drummond, can you respond to this?
I don’t like my green seat, but, hey, at least it is an old one.
Yeah, I just spoke to Mark, and he said that he uses a Dremmel tool to make a slit in the top of the bolt, and then hold it in place with a regular flathead screw driver. Then do the same for al the rest of the bolts.
Someone will come up with a solution that is inexpensive and straight forward, maybe even the unicycle.com folks. It sounds like Mark is turning the carriage bolts into roundhead slotted screws. If they have sorted the problem out, perhaps a hardware kit will be soon available that can be used with minimal tools. It’s hardly cause for panic, just another short delay before it’s easy to make an airseat conversion again.