Sentinel1

Finally got the SL. It's the lightest bike I've ever owned.

Got to get used to the double tap Sram trigger shifter though..its the first time ive ever used one.

Got those wonderful American classic hubs that spin forever. On Kinetix pro X wheels.

Duragrouch

Nice looking bike. Can't remember the last time I've seen a large-flange rear hub. Did those hubs come standard? I like the one-piece (non-telescoping) handlebar riser, T-topped (I think, hard to see), and the bars swinging fore/aft, looks like held with bolted double-clamps (again, hard to see). Tern makes a hand-cammed double clamp to easily adjust on the go, but it's pretty heavy.

Fentuz

they are syntace stem clamps. 40mm but there are some rare 50mm available for specialist.

https://www.syntace.com/en_GB/produc....4-clamps?c=79

the handle post exist in black from speed TT or silver from the Mu SL

wheelset used to be Kinetix comp pro available on speed TT and MuSL which Dahon is not allowed to use anymore as trademark went to tern as part of the divorce settlement.

I rode gravel, dry offroad with these parts and it was much stabler than the original telescopic setup.

Sentinel1

Thanks I'm loving it. Yes the hubs are GORGEOUS on those kinetix pro wheels. Basically frictionless. The front wheel will spin for over 13 minutes. The handlebars sit on a syntace adjustable bracket. So you have 40mm adjustable height. And can adjust it to suit your desired posture better. Forward and lower to be more aggressive etc.

It's my new favourite folder. So light. Only 19.4lbs w/o pedals. Fully loaded with a stand bike computer. Cellphone holder. Lights. Drink bracket. And wider VEE speedster tires. It's still under 23lbs.

Fentuz

just don’t. Per dahon dealer, the rims crack when fitted with tyres wider than 35mm and should not be over 90psi

Sentinel1

Who told you that? The speedsters are 38mm. There's a guy on youtube who put 55mm maxis hookworms on his SL. I never have over 85 PSI

Sentinel1

Who told you that? The speedsters are 38mm. There's a guy on youtube who put 55mm maxis hookworms on his SL. I never have over 85 PSI

Fentuz

ch white who was the main dahon dealer and bought dahon europe stock when dahon europe went bust…

Sentinel1

I will see how it goes. 38mm isn't too over 35mm. I would never go bigger than that. And if they don't sit well after a few weeks. I will change them out for Continental urban 32mm

Fentuz

contact urban 32-406 is the best tyre, i have had on these rims for the last 5 years

Duragrouch

Interesting. My instinct would be that if wider tires allow lower pressure, that would put less stress on the rims (and I assume you mean the tube pressure between the rim sidewalls pushing the sidewalls apart and cracking due to that), but I could be wrong. Maybe larger tire sidewall area means for same pressure, more force to push outward on rims.

Fentuz

from discussion with dealer, the cracks tend to happen by the spoke nipples at the rim apex (stress raiser).

i also understand that these wheels were supplied in 2007 with (edit) stelvio and durano soft supple tyres in 28-406 @120psi max and from 2008, “allowed” kojak 35-406 @90psi max which are supple too.
however, some users pumped these up over 90psi as people did with road bike back in the day or/and fitted marathon 35-406 which are super rigid and created a fair load on the rim and when going through bumps and pot holes, stressed the rim leading to cracking…

just like suspension mount on cars when fitted with strong springs and big rims with low profile tyres….

basically, lack of compliance

https://www.world-wheels.co.uk/speedpro.htm
https://www.world-wheels.co.uk/09_musl.htm

tds101 

Oh man... You listed a WORLDWIDE DAHON DEALER!!! Too bad they apparently no longer exist...

Fentuz

like most dahon things… new models are not great, distribution network is not great… i cannot see the brand sustainability but that s another subject

Jipe

Often, race rims like the one on these race oriented wheels with very few spokes are narrow and do not allow wide tires (I do not see any reason to put so few spokes on a folding bike wheel, the weight saving is small and it reduces the wheel strength, it may look great but its stupid, it only causes problems).

What is the internal width of these rims?

Fentuz

14mm

I agree, on a frnt wheel, it is just ok. On rear, it is playing with fire. The tern kinetix seem stronger but expensive.

the litepro are not bad but @ £70 per wheelset, you get what you pay for…

Jipe

Schwalbe has a table with the recommended tire width in function of the inner rim width, its an extension of the ETRTO table but it starts at 15mm inner rim width, 14 is not in the table!

Ultra narrow rims as ultra narrow tires are obsolete, based on multiple experiments, wide tires and wide rims have much better performances than narrower.

Duragrouch

Interesting. Assuming a double-wall rim, both the rim apex and inner wall could be stressed in lateral tension under tube pressure, or, the inner wall is in lateral tension and the apex is in lateral compression due to the cantilevered load on the other side of the inner wall. However, in the latter case, that compression load at the apex could be trying to bend the apex tighter, which could fatigue it, especially on the outside of the apex bend. Interesting load case.

Automobile suspension compliance: Tell me about it. I don't like very low profile tires. Heck, when the Opel Manta (GM Germany) got imported to the USA in the early 1970s, the roads here were a lot less smooth, and the carmakers had just upped tire pressures to 35 psi for lower rolling resistance for better fuel economy, and I heard from someone in the industry older than me, that they were breaking suspension parts and where they attached. Now, you see cars that are "slammed", lowered onto the bump stops, and, the wheels spaced way outward ("stanced"), those idiots have no idea the stresses they are putting into the suspension. They don't care. Same for very lifted trucks.

Fentuz

yes, i cannot agree more and @etrto 14-406, 35c is the limit but, thanks to conti urban contact, 32-406 is really good with this rim @50 psi with my 66-69kg

Jipe

Anyway, the narrow tires were chosen due to lower aerodynamic resistance but bike manufacturers discovered that a wide tire with a matched wide rim provides an as good aerodynamics, so no reason anymore to use ultra narrow tires+ultra narrow rims like on this old Dahon MU SL folding bike.

Schwinnsta

The chart is bogus in my experience. If you can mount the tire, it will work. I have been riding with 406-50 and 406-52 on Zizzo with 14 opening.

Jipe

The ETRTO table is and ISO standardized table defined by a panel of experts.

Schwinnsta

Well I am just a single source, but I have never seen that violating this table has had consequences. It does change the profile to a more round shape than U shape, but I can't see any problems. Now, if you over pressurize the tire, I could see that effecting the rim. If I run into problems I will post, but so far nothing. By the chart, Zizzo should have supplied rims with at least 17mm for the 40mm tires supplied.

Jipe

Indeed, the narrow rim changes the tire profile to a round shape.

If the rim is really narrow, this round shape only rest on the rim on a small part of the round and when cornering, there is big lateral tire shape deformation (the tire is pushed on one side of the rim) which is even bigger if the tire pressure is low.

Schwinnsta

Maybe, but where are the bodies?