Author Topic: Mondince FM356 61mm tire clearance  (Read 66742 times)

ains

Re: Mondince FM356 61mm tire clearance
« Reply #75 on: June 26, 2026, 01:21:11 PM »
That was my plan, but I wanted to check here first. Sometimes someone already has the answer, which saves Jack from answering the same questions twice.
Going back to the information Jack shared about the headset setup:

"FM356 is standard FSA headset system. It is 52mm ID and 56mm OD."

Secondly, regarding the BB-to-front-axle distance increase and the potentially higher rake fork:

"We have changed the front wheel distance to 600mm for size S. And we may do a bigger rake fork. But we need customer's advice for this.
We did not know whether the 65mm rake good for this bike frame."


It looks like they went with the suggestions. I'm actually quite curious — how do they plan to gather customer feedback regarding that bigger rake fork? Has Mondince did somethig like that before?

As far as I understand they are listening to what potential buyers tell them. And that is very good! I told Jack several times that the current pedal to tire distance in size S is tooooo small and advised him to enlarge it. I think that I am not the only one who told Jack about it. Finally they decided to enlarge this distance to 600 mm. I think that we need to find out if 65 mm rake is good for us or not and tell Jack what we think about it.
« Last Edit: June 26, 2026, 02:14:02 PM by ains »

ains

Re: Mondince FM356 61mm tire clearance
« Reply #76 on: June 26, 2026, 01:35:42 PM »
That was my plan, but I wanted to check here first. Sometimes someone already has the answer, which saves Jack from answering the same questions twice.
Going back to the information Jack shared about the headset setup:

"FM356 is standard FSA headset system. It is 52mm ID and 56mm OD."

Secondly, regarding the BB-to-front-axle distance increase and the potentially higher rake fork:

"We have changed the front wheel distance to 600mm for size S. And we may do a bigger rake fork. But we need customer's advice for this.
We did not know whether the 65mm rake good for this bike frame."


It looks like they went with the suggestions. I'm actually quite curious — how do they plan to gather customer feedback regarding that bigger rake fork? Has Mondince did somethig like that before?

Here is what AI is advising to tell Jack (see screenshots). Could somebody who is skilled in bike geometry comment on those advices?
« Last Edit: June 26, 2026, 02:01:11 PM by ains »

Vesryn

Re: Mondince FM356 61mm tire clearance
« Reply #77 on: June 26, 2026, 03:02:58 PM »
Your line of thinking aligns perfectly with mine. Increasing the fork rake from 50 mm to 65 mm would drastically alter the bike's handling dynamics, completely deviating from the frame's intended design.
The reality is that toe overlap is mathematically inevitable for most size S road and gravel frames, especially when pushing into monster-gravel territory. To prove this, we have to analyze two distinct tire scenarios on a size S frame with a 600 mm front-center dimension (BB-to-axle, dimension "I") and a standard 170 mm crankset (like my Shimano GRX):

Case 1: NO-Clearance Setup (2.25" Tires)
Tire Diameter & Radius: A 2.25" tire has an approximate diameter of 740 mm, giving it a 370 mm radius.
Available Clearance: 600 mm (Front-Center) - 370 mm (Radius) - 170 mm (Crank) = 60 mm !
Result: This leaves exactly 60 mm of space from the pedal spindle (cleat center) to the tire.

Case 2: Full Monstrous Toe-overlap Setup (2.4" Tires)
Tire Diameter & Radius: A 2.4" tire bumps the diameter up to roughly 750 mm, or a 375 mm radius.
Available Clearance: 600 mm (Front-Center) - 375 mm (Radius) - 170 mm (Crank) = 55 mm
Result: This leaves only 55 mm of space from the pedal spindle to the tire.

Using my typical real-world setup: Shimano XC5 shoe (size EU42) paired with PD-M540 pedals—the distance from the cleat center to the tip of the shoe ranges between 88 mm and 108 mm, depending on cleat adjustment.Even in the most optimistic, hypothetical scenario—running the smaller 2.25" tire and slamming the cleat all the way forward (which is not recommended for proper bike fit)—we are still short by 28 mm (60 mm - 88 mm).To completely eliminate this 28 mm deficit by stretching the frame, you would have to increase the reach so much that the front-center (dimension "P") would enter L/XL sizing territory, rendering the frame entirely unrideable for a size S rider.

In my specific case, I run my cleats slammed all the way back, meaning I need 108 mm of clearance from the spindle to the shoe tip. The math leaves no room for compromise:
With 2.25" tires: I will experience a massive 48 mm toe overlap (60 mm - 108 mm).  :(
With 2.4" tires: The overlap increases to 53 mm (55 mm - 108 mm).

There is simply no escaping the physics here. While eliminating toe overlap is a great goal on paper, forcing it onto a size S frame designed for high-volume tires is mathematically impossible without fundamentally ruining the bike's proportions and handling. In this size category, massive toe overlap is a reality we probably just have to accept.

EDIT to prevent double posting.

OK, I had a look at some gravels for that bb-to-axle distance.

Grizl CF XS (pre 2024) - 595 mm
Grizl CF XS - 625 mm
Grail CF XS - 604 mm
Topstone 47 - 601 mm
Topstone 51 - 605 mm
Checkpoint 54 - 606 mm
Diverge 54 - 615 mm
Revolut S - 607 mm
Addict s/52 - 608 mm
Locally popular gravel AL S - 609 mm

Grizl is well known to be designed long and to be used with short stem.
« Last Edit: June 26, 2026, 03:39:14 PM by Vesryn »

YipYip

Re: Mondince FM356 61mm tire clearance
« Reply #78 on: June 26, 2026, 05:06:16 PM »
I usually don't write much, but i thought i might as well give my opinion, if it could influence the way this bike turns out. In my opinion toe overlap is a way smaller problem than people make it to be. Given how far you need to turn the handlebars for the wheel to be close to you foot, for it to actually hit while turning and pedaling the speed needs to be really low. I have a bit of toe overlap on my road bike, and im a totally sure, whenever i feel the need to pedal through a turn,  (i want to go fast) the pace is way to high for me to be turning my handlebars enough for it to be a problem. So what im trying to say is, i would much rather have the steering of a 50mm fork than the clearance of a 65 mm fork, even though im in between sizes and might end up with a size small.
Might just be my lukewarm take, but if anyone is planning on summarizing this thread to Jack, i thought it would be worth to mention, since i am pretty interested in the frame.

ains

Re: Mondince FM356 61mm tire clearance
« Reply #79 on: June 27, 2026, 02:04:26 AM »
Just compared the geometry of Mondince fm356 in size S with 700x61 tires and Spcycle SP028 in size S with 700x61 tires. Spcycle have a bit longer reach that gives the tire to pedal spindle distance of 70 mm. So probably enlarging the reach a bit or slackening the headtube angle could be a good solution to avoid toe overlap if it is still possible to change the geometry of the frame.

YipYip

Re: Mondince FM356 61mm tire clearance
« Reply #80 on: June 28, 2026, 06:19:43 AM »
I usually don't write much, but i thought i might as well give my opinion, if it could influence the way this bike turns out. In my opinion toe overlap is a way smaller problem than people make it to be. Given how far you need to turn the handlebars for the wheel to be close to you foot, for it to actually hit while turning and pedaling the speed needs to be really low. I have a bit of toe overlap on my road bike, and im a totally sure, whenever i feel the need to pedal through a turn,  (i want to go fast) the pace is way to high for me to be turning my handlebars enough for it to be a problem. So what im trying to say is, i would much rather have the steering of a 50mm fork than the clearance of a 65 mm fork, even though im in between sizes and might end up with a size small.
Might just be my lukewarm take, but if anyone is planning on summarizing this thread to Jack, i thought it would be worth to mention, since i am pretty interested in the frame.

Maybe a 55mm fork would be the perfect middle ground.

ains

Re: Mondince FM356 61mm tire clearance
« Reply #81 on: June 29, 2026, 03:27:28 AM »
Maybe a 55mm fork would be the perfect middle ground.

Just asked Jack about offset and he wrote me that front to centre distance in size S is enlarged to 600 mm and the fork offset is left to be 50 mm. So probably some changes were added to frame geometry.

Hazardman_69

Re: Mondince FM356 61mm tire clearance
« Reply #82 on: June 29, 2026, 05:28:25 AM »
TanTan have just posted "ISO" style testing videos on their Instagram for their new 61mm clearance frame, apparently called "GR356". This looks to be the same as this Mondince which would make sense given how it worked when the FM346 came out. They haven't posted any geometry yet so it will be interesting to see what the new, longer front centre, geometry is like.

xcelrec

Re: Mondince FM356 61mm tire clearance
« Reply #83 on: June 29, 2026, 07:35:53 AM »
TanTan have just posted "ISO" style testing videos on their Instagram for their new 61mm clearance frame, apparently called "GR356". This looks to be the same as this Mondince which would make sense given how it worked when the FM346 came out. They haven't posted any geometry yet so it will be interesting to see what the new, longer front centre, geometry is like.

Comes from the same factory, so will be the same frame (was confirmed by mondince). Also got some bad and good news from them.

Bad news - they dropped the riser bar project, apparently what ever they designed wasn't up to standards to they won't sell for now.

Good news - mass production will start in approx. 4 days, it's 625 usd per set incl. frame, fork, seatpost, axles headset, frame bag. default color black matte or ud matte.

As others already mentioned only size s was adjusted, rest stays the same.

ains

Re: Mondince FM356 61mm tire clearance
« Reply #84 on: June 29, 2026, 04:23:34 PM »
Comes from the same factory, so will be the same frame (was confirmed by mondince). Also got some bad and good news from them.

Bad news - they dropped the riser bar project, apparently what ever they designed wasn't up to standards to they won't sell for now.

Good news - mass production will start in approx. 4 days, it's 625 usd per set incl. frame, fork, seatpost, axles headset, frame bag. default color black matte or ud matte.

As others already mentioned only size s was adjusted, rest stays the same.

Probably that mean that some day this frameset will be presented on AliExpress, because most ( if not all) TanTan frames are presented on AliExpress.



Update: Mondince and TanTan wrote that they will not going to sell it on AliExpress☹️
« Last Edit: June 30, 2026, 11:58:46 PM by ains »

ains

Re: Mondince FM356 61mm tire clearance
« Reply #85 on: June 30, 2026, 11:55:26 PM »
Mondince made update of S size. They made top tube 1 cm longer. Now the tire to pedal distance is 56 mm instead of 47 mm and that is still not enough to avoid toe overlap☹️ I asked them to slacken headtube and enlarge front centre distance more but Jack wrote that they will not make frame longer. So probably for me it is better to buy M frame instead of S unfortunately☹️
« Last Edit: July 01, 2026, 03:28:25 AM by ains »

ains

Re: Mondince FM356 61mm tire clearance
« Reply #86 on: July 02, 2026, 09:05:30 AM »
Tan Tan bicycle factory wrote two days ago in their Instagram account that frame will be available in 25 days.

dolph

Re: Mondince FM356 61mm tire clearance
« Reply #87 on: July 02, 2026, 05:15:38 PM »
Does Jack already take orders for the frameset or we need to wait?

ains

Re: Mondince FM356 61mm tire clearance
« Reply #88 on: July 02, 2026, 10:22:37 PM »
Does Jack already take orders for the frameset or we need to wait?

I’m waiting until somebody build bike on this frame and give us measurements of tire clearance with 29x2,4 tires🙂
« Last Edit: July 02, 2026, 11:02:59 PM by ains »

Aerosoul

Re: Mondince FM356 61mm tire clearance
« Reply #89 on: July 03, 2026, 05:14:49 AM »
Same here. I also want to see the colours first.

I wish they could build the sizes, fit them with a groupset, and show the colours so that we can see how the bike will look like fully built