tammons

Will 700 rims with fat tires fit on a Trek 830?
Thinking 700x35 rims and 700x55 tires.

Andrew R Stewart 

Back in the day is wasn't uncommon to see a MtB used on the road with 700x23/25 wheels/tires. Of course the OEM cantis (or current linear brakes)can't be used so back then we would mount a side pull caliper in the fender mounting holes. This was before the advent of suspension though.

The 23/25 wide 700c tires would be slightly larger in diameter (or as the frame/fork cared, radius) and fit within the frame/fork well enough. I suspect that a tire with 30+ more mms of radius would likely contact the frame/fork. Of course the real answer is discovered by trying it. If you have friends with common hybrid bikes you could borrow their wheels (typically 77 x 35/38 tires) and really find out on your specific bike. Then return here and post your findings. Andy

tammons

I have a set of 700c wheels and a set of 700x35 tires, so easy enough to check once I get the frame.

However what I really want is a big cushy tire.

I might have to stick with 26 wheels and swap out rims.
I know that with 26 rims, 26x60 tires will fit.

pdlamb

What does it currently have on it? My daughter had an 830 (until she outgrew it), but it had 26". Brakes wouldn't have worked with 700 wheels.

bikemig 

If what you are looking for are fat, cushy tires, then you should stick with 26 inch wheels.

tammons

No wheels on it so far. I am buying a frame with everything except 2 wheels and the seat.
Will cold set the rear triangles to 130mm. And swap it over to a 1x11 speed.

I have an extra set of 700c wheels with Shimano Ultegra hubs.
I will most likely end up using the hubs to build new 26 wheels, depending on how the 700 wheels look.

bikemig 

Try out your existing wheels and see if you like the clearane with 35c tires. Also will the cantilevers (this bike does have cantilevers, right) work?

Leebo

Some problems may arise. Wonky handling. Got disc brakes? Rim brakes? How would those line up? Lower bb and waaaay lower pedals to the ground. Might be better off to get a frame that fits the wheels/tires you intend to use. Not saying It cant work, but plenty of bike that will fit a 29 x2" tire.

2old

Don't know your budget, so why not save the cost of brakes/tires for the 700's and purchase a set of 26" wheels or build up the Ultegra hubs? If necessary, you can locate used 26" wheels pretty inexpensively since that size isn't popular now.

Russ Roth

Why coldset the rear end? It is most likely 130 already and probably 135, not certain I've seen an 830 old enough to be 126. I highly doubt that you will be able to fit a 700c wheel in there with any size tire, could be wrong but doubt it, especially since they either had suspension geometry and came with a suspension fork that won't fit it or its pre suspension geometry and the fork isn't tall enough to add a taller wheel. I'm assuming you're trying to fit it due to having wheels but you're liable to pay more for brakes that will fit it and work well then you will for a decent set of 26" wheels and its not like its hard to find a wide, quicker 26" tire, those are plentiful and cheap on ebay.

tammons

Thats what I am thinking about.

tammons

I am pretty sure the rear is 126mm.
But I will know when I get it.

Will probably go with 26 wheels. Sounds like thats what I will need to keep brake headaches at a minimum, and to fit large tires.

I will wait until I have the frame here before buying anything else. I am curious to see how 700 wheels fit.

jimc101

What year is the bike? the Trek 830 normally (as we don't know exactly what you have) was a lower-end MTB, that means 26"/135mm rear hub https://www.bikepedia.com/QuickBike/...k%20&model=830.

If this is the basic spec, you're not fitting 700c wheels in it.

Really not getting the logic of throwing any significant money at a bike like this and throwing a 1x11 set up on it (with the exception of you had all the parts already/zero cost), as this was a lower-end bike BITD, and any money you would look at putting into it would be far better put into a new bike with the spec you want, as parts of the spec make sourcing modern parts for it harder than it needs to be, like the 1" headset (yes they exist, but harder to get than a 1 1/8"), if going 1x11, you will probably need new brake levers, again, getting rim brake levers now is harder than it used to be.

Additionally, the handling will be bad vs a modern bike, yes it can be improved by throwing parts/money at it, but it will always be a compromise vs a modern bike

tammons

87' 830

I already have 95% of the parts to put it on the road.
And I already have built 700 wheels with an 11 speed cassette and 35 tires, so I will try them out.
If I dont like that I will use those hubs and build a set of 26 wheels.

If I do keep it with 700 wheels, eventually it will end up like this or similar...

https://forum.bikeradar.com/discussi...to-gravel-bike

LesterOfPuppets

700 x 55 is gonna be a no-go. You could theoretically get a replacement fork for it that would run the wheel/tire combo you're looking at, but I wouldn't suggest doing so.

Here's a Park Pre 26er with 20mm rims and 32mm tires fitted:

LesterOfPuppets

There's a slight chance it might be 130mm in the back already, being 1987.

I'd get a more modern frame if you really want to run 2.25" 29er tires

tammons

I have considered it. All the 830 components that came with the frame were upgraded, so I will probably sell them off on Ebay.

tammons

Reporting back for future reference.

I think this frame has already been cold set. It is 135mm now and will stay that way.
From what I read the rear dropouts should have originally been 126mm.

But all the components were upgraded at some time, so I assume they did the framework then.

700x35 Shwalbe Mondial tires fit this frame fine.
I could probably go up to 40, barely, and depending on the tire and tread.

Hooked up the 7 speed MTB trigger shifters to the 11 speed deraileur and got it working a bit.

Took it out for a ride with no brakes - LOL.

Its nice, but twitchy. And the crank is high.

And I need wider/fatter tires for the loose sand around here.

So, I think I will build or buy a set of 27.5 wheels.

Thanks for all the comments.

LesterOfPuppets

Yeah, you'd probably have to remain brakeless running much more than 35mm 700c, but bmx calipers like Odyssey 1999 might fit, you'd have to measure brake bolt hole to brake track distance. They're barely brakes though, not very strong.

With 27.5 some Vs and cantis have room to push the pads up to the brake track with the brakes mounted to the canti bosses. But not all allow that much pad adjustment, it'll be a crapshoot.

The widest tires you can fit between the chainstays would likely be 26" due to the shape of the stays.
​​​​

tammons

Since I am building (or buying) new wheels, I am going to change hubs to disc brake hubs and work the brakes out later.

zjrog

So, I have a 1989 Trek 950. Probably very close to your 830. I fit a couple different wheels and tires for you to see.

On the left, knobby 26x1.95 MTB... Middle, road wheel with 700x25 tire. Note the the brakes will not reach the rim. And right, 700x45. Note that the brakes do not rack the rim, also runs out of space, the tire hits the crown, and the axle is not secure in the dropouts.

So choosing a 700c wheel is not going to let the brakes hit the rim. Choosing a 700x32 or maybe 35 might still fit under the crown, or in the rear triangle, your choices for braking diminish rapidly.

I I don't have a 700cX35 to check the fit on my 950.

tammons

Your front forks look tighter than mine, but I will have to look again.

Also, my calipers look like there is enough adjustment for 27.5 wheels

tammons

This is what I ended up with for now...

While waiting on spokes to rebuild my 700c Raleigh wheels, I put my old Weimann 605 brakes on the 830. They work fine for now, until I get my new 27.5 rims, hubs, and spokes. Those wheels will be built with disc hubs, and rim brake rims so I can transition to disc brakes later. I will use the MTB calipers that were on the Trek for the 27.5 rims until I go disc brakes. They have enough adjustment.

Removed the cable for the front derailleur/trigger shifter. Dont need it.

Rode it and its fine, only I want larger tires. The new 27.5 tires will be as wide as will fit.

Have the 7 speed trigger shifter that came with the frame adjusted to run the 7 lowest gears.

I will probably need to change to a 32 or 36 crank gear, but I will do that later.

This is with 700c wheels and Schwabe Mondial 700x35 tires.

trailangel

YOu won't be transitioning that bike to disc brakes anytime later...
IMHO get a new bike/frame for disc brakes and 27.5 wheels.

tammons

I may opt for a new frame with better geometry, but disc brakes are doable on the 830 frame.
Its been done before.