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Downtube folding bike

Old 04-21-07, 09:21 AM
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anyone know if the bottom bracket on the IXNS model is sealed?
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Old 04-22-07, 12:41 PM
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Originally Posted by dxfyo
anyone know if the bottom bracket on the IXNS model is sealed?
The one I got about 3 months ago was not the sealed variety.
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Old 04-22-07, 01:04 PM
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Originally Posted by invisiblehand
Hey Yan,

I searched through this thread for wheelbase and got an estimate for a 20" Downtube as 42.5 inches. Do you have a wheelbase estimate for the Mini?

Thanks.
Sorry for not responding sooner. I missed this post. It is 37.5 inches

Thanks,
Yan
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Old 04-22-07, 09:36 PM
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Originally Posted by SesameCrunch
The one I got about 3 months ago was not the sealed variety.
Thanks,
I'm thinking of putting in a shimano sealed bb, but my current one still rides so smoothly.
Smoother than my 07 dahon speed d7, I might change that one before I change this.
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Old 04-22-07, 11:03 PM
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Originally Posted by dxfyo
Thanks,
I'm thinking of putting in a shimano sealed bb, but my current one still rides so smoothly.
Smoother than my 07 dahon speed d7, I might change that one before I change this.
Why not do both? It's a cheap upgrade. Also, it would give you a chance to properly grease the BB shells, which has been pointed out in this thread as a concern with DTs.
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Old 04-23-07, 07:31 AM
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Originally Posted by downtube
Sorry for not responding sooner. I missed this post. It is 37.5 inches

Thanks,
Yan
No problem Yan. Thanks for taking the time to respond.

-G
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Old 04-23-07, 09:34 AM
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Originally Posted by SesameCrunch
Why not do both? It's a cheap upgrade. Also, it would give you a chance to properly grease the BB shells, which has been pointed out in this thread as a concern with DTs.
Will do,
To use the stock crank, the bb should be a 68x115 right?
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Old 04-23-07, 10:46 AM
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Originally Posted by dxfyo
Will do,
To use the stock crank, the bb should be a 68x115 right?
According to post #1085, 68x115 is the correct size.
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Old 04-23-07, 11:03 AM
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Thanks,
Nashbar has the un54 for $20 and un73 for $28, anyone know is there a big difference?
as in weight or otherwise.
btw it's their last day for free shipping code FSP833.
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Old 04-23-07, 11:24 AM
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Cog & Chain Ring Options

Originally Posted by WrencherWOAC
Don't expect much change:
48/25 * 20 = 38.4
48/23 * 20 = 41.7

less than 1 mph at normal cadence

40/23 * 20 = 34.8
24/23 * 20 = 20.9
Thanks for calcs.
My point is only that it's easier and sometimes cheaper to swap the 23t cog for the 25t - the largest available for the S-A-8, and only $7 - $15 new - than to start fooling around with chain rings & chain guards.
(Also, my experience is that you can't make such changes purely on the calcs, that you have to test drive them one-by-one to see what you can live with.)
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Old 04-23-07, 07:12 PM
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Originally Posted by dxfyo
Thanks,
Nashbar has the un54 for $20 and un73 for $28, anyone know is there a big difference?
as in weight or otherwise.
btw it's their last day for free shipping code FSP833.
I believe the un73 has a hollow square taper axle and therefore lighter.
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Old 04-23-07, 11:24 PM
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Thanks for the nice feedback. Siena was great, but we actually enjoyed Volterra a bit more, since it seemed more casual. But Giglio was our favorite, since it was out of the way and hadn't been overrun by the summer tourists yet.

We just left the suitcases at our Hostel in Florence - they let us store them for free! So that worked fine.

I still need to finish getting the rest of the pictures online (and the blog report). I will post here again when done (I'm too busy trying to get a frozen BB out of an old Fuji Mtn Bike I'm converting to singlespeed - I've spent about 6 hours drilling and grinding it so far, and finally may be getting close!).

Originally Posted by WrencherWOAC
We really enjoyed your pics on Flickr. Great landscape shots. Brought back memories as we have been most the places. Isn't Sienna a wonderful place for a change? The bikes are set up very nicely. Looks good. Where did you store the travel cases while you were touring?
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Old 04-24-07, 06:51 PM
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Bent deraileur hanger.

I thought the new DT uses a thicker hanger, which is less likely to get bent. I just received my DT IXNS (my first folder) today and found the hanger is bent. The pulley is pointing inward. Quite obvious. Any suggestion on how to make it straight?

Thanks. I really want to ride on it as soon as possible.
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Old 04-24-07, 07:02 PM
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Originally Posted by Kabir
Bent deraileur hanger.

I thought the new DT uses a thicker hanger, which is less likely to get bent. I just received my DT IXNS (my first folder) today and found the hanger is bent. The pulley is pointing inward. Quite obvious. Any suggestion on how to make it straight?

Thanks. I really want to ride on it as soon as possible.
My DT came shipped with a bent hanger but the LBS was able to bend it back quite easily...I haven't had any problems with it since.
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Old 04-24-07, 10:23 PM
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...found the hanger is bent. The pulley is pointing inward. Quite obvious. Any suggestion on how to make it straight?
A 12" crescent wrench makes bending a bent derailleur hanger easy. Remove the derailleur, close the jaws of the wrench on the flats of the hanger. For vertical bends just move the wrench handle up or down. For horizontal bends I put a large screwdriver though the hole in the end of the wrench handle and then use the screwdriver handle to torque the wrench. You want the derailleur pulleys to "point" towards the chainrings in when the chain is on both the large and small sprockets on your freewheel/cluster. Do so at your own risk, but it should work pretty well. You can also take a 2x4 and cut a slot in it with a saw that is the width of your hanger... The key is a tight fit on the hanger and a long lever arm.
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Old 04-26-07, 06:41 AM
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I'm nearing 100 miles and maybe 30 fold/unfolds on my DT, and have a couple quick mechanical questions.

At the hexnut end of the QR for the frame hinge, there seems to be some kind of black spacer or washer "inside" the threads. The hexnut was VERY loose and the black spacer(?) looked a little mushed or displaced before I tightened the nut. Do I have a bad part here? I didn't think the QR hexnut should get loose, maybe needs some locktite or similar.

Second, it has gotten MUCH harder to insert/remove the handlebar stem into the headset (?) tube. Same with adjusting the seatpost up/down every fold. Any suggestions here? Just a HUGE amount of friction and effort needed to move the tubes vertically while twisting.
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Old 04-26-07, 07:13 AM
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Does Downtube the company carry product liability insurance?

TCS
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Old 04-26-07, 09:15 AM
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Originally Posted by tcs
Does Downtube the company carry product liability insurance?

TCS
I wonder how anyone other than a Downtube representative could answer this question. Maybe it would be more proper to ask this in a private message instead of a public forum? The answer is yes.

Yan
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Old 04-26-07, 09:34 AM
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Originally Posted by JugglerDave
I'm nearing 100 miles and maybe 30 fold/unfolds on my DT, and have a couple quick mechanical questions.

At the hexnut end of the QR for the frame hinge, there seems to be some kind of black spacer or washer "inside" the threads. The hexnut was VERY loose and the black spacer(?) looked a little mushed or displaced before I tightened the nut. Do I have a bad part here? I didn't think the QR hexnut should get loose, maybe needs some locktite or similar.

Second, it has gotten MUCH harder to insert/remove the handlebar stem into the headset (?) tube. Same with adjusting the seatpost up/down every fold. Any suggestions here? Just a HUGE amount of friction and effort needed to move the tubes vertically while twisting.

My hinge on my Mini got a little loose after several folding cycles. I tightened it - no problem now. Anything that moves, like hinges or other interfaces, is going to need periodic service. Nothing is maintenance free.

Try taking out the seat post and stem, wipe them down and then either run some water through the tubes or find a way to run a rag through them (similar to cleaning a gun barrel). I think you will find the reason for the increased friction is dirt and nothing more. Even if it doesn't look particularly dirty, it probably is.
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Old 04-26-07, 09:46 AM
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Edit: Pretty much what Polaris said

Originally Posted by JugglerDave
I'm nearing 100 miles and maybe 30 fold/unfolds on my DT, and have a couple quick mechanical questions.

At the hexnut end of the QR for the frame hinge, there seems to be some kind of black spacer or washer "inside" the threads. The hexnut was VERY loose and the black spacer(?) looked a little mushed or displaced before I tightened the nut. Do I have a bad part here? I didn't think the QR hexnut should get loose, maybe needs some locktite or similar.
I'm not 100% sure exactly where you are describing here. The quick release will loosen over time and need periodic tightening. There is a black spacer in the quick release that gets smashed over time. Mine was working fine with periodic tightening, but eventually I just replaced it with a higher quality quick release. I assume the nut will need replacing after awhile, those types of nuts do very well for a while not moving, but if you loosen and tighten them a lot eventually the plastic (or what ever it is on the end of it) will get worn out. Those types of nuts should be very easy and cheap to replace, a little BLUE loctite certainly wouldn't hurt. Just don't use anything stronger than blue because you need to be able to adjust it.

Second, it has gotten MUCH harder to insert/remove the handlebar stem into the headset (?) tube. Same with adjusting the seatpost up/down every fold. Any suggestions here? Just a HUGE amount of friction and effort needed to move the tubes vertically while twisting.
I've just been noticing this recently, because I have been cycling in the rain and road muck. What solved it for me was a very thorough cleaning of the seatpost, inside of the seat tube, handle bar stem and inside of the folding stem. Don't oil or grease, just clean it really well.

I hope this helps.
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Old 04-26-07, 11:08 AM
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Originally Posted by Loch
I'm not 100% sure exactly where you are describing here.
When I look directly at the hexnut. The bolt is stainless steel. The hexnut is stainless steel. INSIDE it looks like a black round plastic 'sheath' surrounding the bolt but within the threads of the hexnut. Does this make sense?

anyway, I'll try a thorough cleaning of the various posts and stuff this weekend.
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Old 04-26-07, 12:18 PM
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Originally Posted by JugglerDave
When I look directly at the hexnut. The bolt is stainless steel. The hexnut is stainless steel. INSIDE it looks like a black round plastic 'sheath' surrounding the bolt but within the threads of the hexnut. Does this make sense?

anyway, I'll try a thorough cleaning of the various posts and stuff this weekend.

In this image the portion you are talking about is white, correct?

That is the part of the nut that keeps it in place, if the nut moves freely (if you can tighten it and loosen it with your fingers) than it is worn. You should be able to pick up a similar metric nut at a hardware store for just a few cents.

Incidently, I think I run over to the store and pick up some spares for myself. I believe they are called nylon insert lock nuts.
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Old 04-26-07, 01:03 PM
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Originally Posted by Loch
In this image the portion you are talking about is white, correct?

That is the part of the nut that keeps it in place, if the nut moves freely (if you can tighten it and loosen it with your fingers) than it is worn. You should be able to pick up a similar metric nut at a hardware store for just a few cents.
That's it! I guess that is a part that wears quickly when used on a bicycle QR. I'll have to see how quickly the nut gets loose now that I've tightened it.
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Old 04-28-07, 02:59 PM
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Originally Posted by JugglerDave
Second, it has gotten MUCH harder to insert/remove the handlebar stem into the headset (?) tube. Same with adjusting the seatpost up/down every fold. Any suggestions here? Just a HUGE amount of friction and effort needed to move the tubes vertically while twisting.
Follow-up: I took out the handlebar and did a good cleaning there, that helped. I took out the seatpost and there was tons of gray metal 'dust' from all the scraping inside. I shined a flashlight inside and saw that there were 3 or 4 'bump ins' protruding into the seat tube where the welding of the frame took place. One big one was where the horizontal part of the frame connects, and two smaller bumps near the bottom bracket. I was able to 'shave' the bumps down with a few tools and some Dremel ingenuity, and the seatpost travel is much smoother now. But now I know what scratched up the seatpost something crazy!
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Old 04-30-07, 08:38 AM
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Big Apple 20x2.0 on IXNS

Has anyone ever tried that? Does IXNS have enough clearance for 20x2.0 tire?

Thanks
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