Surly Instigator: Steel frame HT + Bafang BBS02 Mid-drive
- Thread starter COAR
- Start date
My rear tire is basically shot and I don't really want to spend $90 on an obscure and nearly obsolete tire size (26+), so I think I'll spend significantly more and convert the bike into a mullet: 29" front, 27.5" rear. If this calculator is accurate, I can run a 130mm 29er fork with minimal changes to the geometry. https://madscientistmtb.com/bike-geometry-calculator/
Fortunately I have a 29er with such a fork - I'm not going to cannibalize it, but that should swap directly over to the Instigator so I can see if this whole mullet thing is worth it.
Fortunately I have a 29er with such a fork - I'm not going to cannibalize it, but that should swap directly over to the Instigator so I can see if this whole mullet thing is worth it.
COAR, I have no beef with mullets. I've run a 27.5/26 setup for years. My Fox 36 and dual crown fork both accept 27.5. A good while back I even ran a 29/26 setup on a Maverick ML-8. I'm just curious about your take on the availability of good 26" rubber.
While not as abundant as the now more common 27.5 and 29, there are lots of good choices available. For example I'm running a Continental Der Kaiser 2.4 X 26 rear on my SC Nomad/BBSHD, and it's been awesome running it tubeless. There are very good Maxxis tires as well as Michelin and others. And as far as the price goes, there are very competitive prices on Amazon and online bike suppliers.
Nothing wrong at all with a desire to go to a 29 or 27.5 setup, but I wouldn't base it on high price or even obsolescence. The power of a motor overcomes some of the rollover and momentum advantages of the larger hoops when you don't have to just rely on human pedal-only power. Options are good.
While not as abundant as the now more common 27.5 and 29, there are lots of good choices available. For example I'm running a Continental Der Kaiser 2.4 X 26 rear on my SC Nomad/BBSHD, and it's been awesome running it tubeless. There are very good Maxxis tires as well as Michelin and others. And as far as the price goes, there are very competitive prices on Amazon and online bike suppliers.
Nothing wrong at all with a desire to go to a 29 or 27.5 setup, but I wouldn't base it on high price or even obsolescence. The power of a motor overcomes some of the rollover and momentum advantages of the larger hoops when you don't have to just rely on human pedal-only power. Options are good.
COAR said:
I'm looking at this pic and wondering how close you'll be to the chainstays assuming the tire moves forward 3/4" or so. Are you going with the same width tire?
https://endless-sphere.com/forums/viewtopic.php?f=6&t=110586&start=25#p1664803
E-HP said:
I was wondering about this too. I've had some fairly burly, not-too-ancient 26", long travel MTB's. When the 650B/27.5 interest arrived, none of those frames would accept a 27.5 tire/wheel of any usable off road size...hence, 27.5/26 mullets which worked great. I thought I saw something in one of COAR's posts here about "new stays or dropouts"...or such. Is he installing something to lengthen wheelbase?
TNC said:
My first full suspension bike was actually a Maverick Durance I built up like 7 or 8 years ago. The ML8/Durance were dream bike status when they were new, it took a while for them to depreciate into my price range at the time.
The "availability" of 26 tires was based on the + sizes, ~2.75-3.0. No doubt I could find something cheaper and better if I step down to the ~2.4" range. I was wanting to stick with a wider tire so I have a bit more cushion in the rear. However In real world usage I don't know how much an extra 1/3" of width actually matters for my purely recreational riding (so I may just settle for a 2.4).
I agree power closes some of the rollover deficiencies of 26 while climbing, but DH is a different story. The Instigator has 2.75x26 and 140mm of travel, while my pedal-only Fuse has 2.6x29 and 130mm. The Fuse goes down much nicer, even with less travel and worse fork.
E-HP said:
The new dropouts let me slide the wheel back nearly an inch so there shouldn't be clearance issues. I would probably go to a 2.6 or so.
TNC said:
Yep this is what I've mostly been mountain biking on lately. I owned the original Instigator a while ago and is largely the reason I bought version 2.0. It's probably one of, if not the, least popular Surlys - I think the retail price on a complete bike was ~$3500 which was a tough sell back in 2014.
So I threw the 29er fork on there and it's definitely a no-go - feels completely wrong. Glad I could try before buying. Well actually all I did was sit on it since the headtube was about an inch too short, but that's enough to know I don't want to go down this route.
Found a shop in NM that shipped me some new 'old stock' Dirt Wizards at a reasonable price. I like the compound and tread pattern on these tires but even though the bead seats very nicely, I don't think these were designed to run tubeless. Sidewalls are fairly thin so I hopefully don't pinch flat the rear [again].
