Raised chainstay frame on budget Trail Bike.

[Retrorockit]

I was in Dicks Sporting Goods and stopped to loook at the bikes. I saw one that had an interesting frame. I guess it's about a $500 MTB. Nishiki Colrado Pro 27.5. HT with 100mm Suntour fork amd 20mm axle I think..
The frame has a raised chainstay on the drive side. It comes with SRAM NX 1x11 setup 2.8 tires, and Techtro disc brakes.. But it loooks like it could go staright to belt drive.
https://www.dickssportinggoods.com/p...hoCysUQAvD_BwE

[ncmired]

Funny you should mention this bike - it does look very interesting for our nefarious purposes, at a great price and not a lot of waste.

Here's a clumsy BBSHD build video, using this bike:

How would you belt it - one speed with one of those cassette single speed conversion kits? Maybe the Sturmey Archer 3spd IGH cassette hub, like one of rider's BBS02 builds? If it were my build, I'd spend a little more and bump up the front rotor to 180mm and maybe a better mechanical caliper.

[Chucknelson01]

Hi, I tried this same build with the bbs02 but used the Luna 30t chain ring where the chain was hitting the elevated chain stay. Did you go thru all of the gears using the stock 46 Bafang ring and had no chain rubbing with the BBSHD? I will try swapping out the ring

[ncmired]

Hi Chuck - I don't own one of these bikes, and didn't make the video.

[Rider]

This frame looks very interesting. I will have to go check out its' geometry...

Chucknelson01 - How in the world could a 30T on a BBS02B possibly hit the chainstay on this bike? The stock chain ring on it is a 30T or larger. Can you post a picture that shows what you claim?

The BBS02B is lighter and has a better cadence than the BBSHD, so the only reason to go BBSHD is if you want more watts or throttle without pedaling IMHO.

[Retrorockit]

The puny bottom bracket get's thrown away for a mid drive. A 29 er would be hard to get the gearing low enough. If I didn't already own 3 bikes i would have one.

[Mr. Bungle]

I LOVE Elevated Chain Stay (or ECS) bikes! No chain slap!

[Rider]

EASY BELT DRIVE BABY!

[ncmired]

How would you tension the belt with that fixed rear dropout? Time for one of the derailleur hanger belt pulleys maybe?

I'd love to get one of these especially at that price, but I've got a frame in a box that I can't afford completing. I'm too possessive to sell anything off.

[Rider]

I’ve seen belt tensioners on FS bikes in Europe. They are usually close to the crank belt ring. No personal experience doing that, as I always thought Gates recommended against it, but maybe that has changed with time, proper tension pressure and a large enough roller that won’t damage the Gates belt internals.

[Superfood Funguy]

Hello! I got this bike on Black Friday special in 2018. Got a bargain - they lost the pedals and and knocked $40 off the sale price of $350. So, I got it for $310! I did some upgrades; replaced the mechanical for hydraulic brakes (Shimano Deore XT) 203MM front, 180MM back; Forte pedals; Race Face aluminum 760mm handle bar; Binary Joystick 50MM stem; KS external dropper post and just ordered a Manitou Markhor fork for it. Total cost including the bike was $1000 almost exactly. I'm REALLY happy with the way it turned out!

I got this bike specifically to install the BBSHD. The motor went in fine and with no problems. I got the Luna 42T aluminum sprocket, but the chain is tight and it rubs on the underside of the elevated chain stay. The stock Bafang fits a little better but still rubs. I ordered the Eclipse to see if it pulls the chain a little closer to the frame and away from the chain stay.

I was wonder (if anybody has any ideas/advice):

1. Has anyone come across this issue on this particular bike? Did the Eclipse solve it?

2. Would the 30T sprocket solve it?

3. It looks like I'll have to lengthen the chain a bit - but maybe not with a 30T sprocket?

I'm pretty much a noob and learned much via YouTube and the forums - Thanks for input guys!

[ncmired]

Hello! I got this bike on Black Friday special in 2018. Got a bargain - they lost the pedals and and knocked $40 off the sale price of $350. So, I got it for $310! I did some upgrades; replaced the mechanical for hydraulic brakes (Shimano Deore XT) 203MM front, 180MM back; Forte pedals; Race Face aluminum 760mm handle bar; Binary Joystick 50MM stem; KS external dropper post and just ordered a Manitou Markhor fork for it. Total cost including the bike was $1000 almost exactly. I'm REALLY happy with the way it turned out!

I got this bike specifically to install the BBSHD. The motor went in fine and with no problems. I got the Luna 42T aluminum sprocket, but the chain is tight and it rubs on the underside of the elevated chain stay. The stock Bafang fits a little better but still rubs. I ordered the Eclipse to see if it pulls the chain a little closer to the frame and away from the chain stay.

I was wonder (if anybody has any ideas/advice):

1. Has anyone come across this issue on this particular bike? Did the Eclipse solve it?

2. Would the 30T sprocket solve it?

3. It looks like I'll have to lengthen the chain a bit - but maybe not with a 30T sprocket?

I'm pretty much a noob and learned much via YouTube and the forums - Thanks for input guys!

Congrats! What 42 tooth sprocket did you get? Was it one of these or the 104BCD sprocket on a spider? The bike has a 30 tooth sprocket originally, if I remember correctly.

On a 68mm bottom bracket, the 42 Eclipse with have a 85mm radius, about 45mm out from the center of the seat tube - this might help to ballpark where the chain will end up.

Rewatching the video I posted above using the stock Bafang 46 pie plate, it does look like the chain come damn close to the chain stay.

[Superfood Funguy]

Thanks for the quick reply! Yes, the original was a 30T.

I got the upgrade sprocket: Luna Aluminum Chain Ring Adapter With 42T Sprocket; option with the kit.

I have the Eclipse on order. Went with the lower price, so looks like I'll have to get the sprocket ordered. The product descriptions were just about identical.

Just put the battery on and working on all the wiring. Gettin' excited!!!

[ncmired]

A lot of us are jazzed over this bike frame and its high-mount chain stay because it solves the wide tire chain stay interference problem with the Bafang gear housing, and hopefully empowers the Eclipse 42/48 chain line fixer magic.

Forge ahead!

[Retrorockit]

Could you post some photos of what fits, and what doesn't, so people will know if it's suitable for their purpose?

[Superfood Funguy]

The install is complete! I still have to "pretty up" the wiring; re-zip tie everything. But, relatively easy install. Took it for a test drive and got it up to 32 mph on flat ground, throttle only! I think I had it i the 7th or 8th gear. The chain is super tight, though. It actually bound up testing the range of gears on the 9th ring, due to too short of a chain. I was able to get it back to lower gears after a bit of finessing.

The "pie plate" is the best fit (over the Luna Aluminum 42T sprocket). It keeps the chain line the best. I ordered an Eclipse 42T Chain ring; anxiously awaiting it's arrival (I guess they're being produced). So, I won't be riding it much until then and until I lengthen the chain. Gotta look up how to do that - doesn't look too difficult.

I'll post more photos when I swap out for the Eclipse chain ring.

[Rider]

To determine proper chain length, note the position of the derailleur in low and high gear, then subtract the stock sprocket teeth from the new sprocket teeth to get a likely increase in teeth. Start there and check the derailleur position in low and high gear to see if it is the same as before. It might be fine with just the additional teeth difference, but if not test it with two more links. Repeat until correct. This method assumes the factory bike was setup correctly to begin with and you don’t have to know anything about bike mechanics.

A smaller chainring should correct the chain touching the lifted rear stay. Please post a picture with a 42T when you get it. Thanks.

[Superfood Funguy]

Just realized...didn’t post a pic of the semi-finished product.

[MIKEinNC]

Great looking build. Is the chain only rubbing when you try to go into the lower (larger) gears ? I believe the cassette is 11-42 tooth; do you find you need to go into those lower gears ? I suppose with the large tires you may. I realize you haven't ridden the bike much yet, so those questions might be premature. These next two questions are for anyone out there who is considering a belt drive IGH setup, as I am: are you aware of a tensioner that is available for the Gates drive ?? It's my understanding that they specifically don't advise the use of a tensioner, but I've also read of people seeing OEM belt drive bikes with a tensioner. Has anyone had experience with installing a belt drive (with or without a mid-drive) on a Trek Stache ? Sorry, I don't mean to hijack your post, I'll be watching it with interest. Thanks, Mike

[Superfood Funguy]

Thanks! It was pretty much rubbing in all the gears with the stock pie plate and the Luna Aluminum 42T. I got the Eclipse 48T and it has pretty much taken care of the rubbing with the exception of the highest three gears.

[Superfood Funguy]

Update on the BBSHD/52V build. Here is the latest with the exception of installing the gear sensor, new fork and (waiting for availability on) the 40T Eclipse chainring.



The Eclipse 48T chain ring is a big step in alleviating the chain rub. It now strikes the chain stay in the highest gears 9-11 only (instead of ALL gears!). I'm waiting for the Eclipse 40T chain ring to become available. I think the smaller sprocket will take care of the last 3 gears from making contact with the chain stay.

I had to replace the chain with a longer one. As you can see, it's just about at the limit when in the lowest gear, still. I think the 40T sprocket will take care of that, too.

Here's a list of the upgrades I've made:

[Retrorockit]

When you say the highest gears do you mean the high speed top gears, or the highest sprockets? I'm looking at his from a commuter/street point of view. Would a 11-36 cassette help? With the tall tires 44-46T chainring would be enough.
Here's a gear/speed calculator to play with.
http://www.bikecalc.com/gear_speed
IGH hubs have an overdrive function that allows smaller chainrings. But the BBSHD can only go down to 40T. Belt drive IGH is still a question mark for this bike.

[Superfood Funguy]

My understanding is the highest gears are the smallest gears, speed. And the "granny" gear would be the largest gear, torque. I just ordered a 42T Eclipse chain ring. I think this will go a long way in helping. The offset is the same as my 48T, but the diameter is 25mm smaller (180mm vs 205mm). I think this might be enough to keep the chain far enough away from contact. Thanks for the bike calc.com link!