helpless

Here is the sad state of affairs:

https://www.flickr.com/photos/4941685...n/photostream/

I did not install the crank backwards. The drive side crank curves towards the frame, and I installed the non-drive side crank so that it also curves towards the frame. The stampings are on the side towards the frame. Here is a picture:

https://www.flickr.com/photos/4941685...n/photostream/

The drive side crank clears the chain stay by 3 mm.

Torchy McFlux

Did you measure the distance from the center of the frame's seattube to the center of the middle chainring like I suggested?

helpless

It's around 43-45 mm.

Torchy McFlux

Frankly, there's no way a crankarm should be that close to a chainstay on a properly designed and built frame. If your measurement is correct and the mid ring is a whole 45mm from the center of the seattube, then the bad design of the frame is to blame.
You can either sacrifice ideal chainline and front derailleur performance by putting a slightly longer bottom bracket spindle in, or return the frame to the manufacturer and demand a refund on a poorly designed product that you unnecessarily have to make compromises for to use.

WillJL

You can buy a bottom bracket with a wider axle. If you are using used parts, there is a possibility that the crank arm or the chainstay is bent.

helpless

I measured it again: 45.5 mm. My error is probably +- 2mm. I can't return the frame now because I need it for a tour I'm doing. If the crank were more outboard, that wouldn't be the worst thing in the world for a touring bike would it?

helpless

All the parts are new.

helpless

All the parts are new. If I buy a 116 mm BB would that mean I get another 9mm of clearance divided by two? So 4.5 mm on each side. Let's say the crank overlaps the chainstay by 1.5 mm, so that would give me 3 mm of clearance? Is that enough?

Or is the crank the problem? Are there cranks that don't curve inward?

Torchy McFlux

It's not ideal, and there's no excuse for it. Who built the frame?
Most 107mm Shimano BBs also come in 110 and 113mm versions. You need to do an exchange, I think. Sounds like you may need to take the whole frame into the shop to make them believe you.

helpless

Rivendell.

My BB is labeled:

IRD - Interloc Racing Design
Cartridge Bottom Bracket

Quad QB-75
CrMO axle/
Alloy cups and body

Length:
107mm

Shell fit:
68mm

I have to go to bed now. Thanks for the help. I'll check back tomorrow.

Torchy McFlux

Just looked it up. Sugino recommends a 113mm BB for the XD600, so the people that sold it to you are wrong. Exchange it for the proper size.

rodentfield

If there's anything you can do to get more clearance, even a mm or two is enough. I've done this on a crank swap for a ss i made. you really don't need a lot of clearance as long as it's not actually touching.

Grand Bois

You bought the wrong bottom bracket. Sugino recommends 113 mm and so does Rivendell. There's no way to make it work. You can't exchange it because you've installed it. Buy the correct BB.

goatalope

Touring bike's chainstays flair out more than traditional road bikes. You can either get a longer spindle, or a different crankset that extends out further, like a mtb crank.

helpless

No. Rivendell recommended a 107mm BB. Then I read that VO recommends up to a 116mm BB with the Sugino XD600 crank, so I asked Rivendell if they were sure the 107mm BB was the correct size. Rivendell's response was:

"THE DESIGNER OF THE BIKE AND OUR HEAD MECHANIC BOTH AGREE ON 107. WHY DOUBT US?"

JohnDThompson 

Why do you doubt them? Just send them the picture...

BCRider

Well, it would seem that the designer or the guy welding the bike screwedup. Clearly the BB axle they recomended so vehemently is not the right size. Or at least not the right size for that crankset.

Time to go and get a 113. Or you may even need the 116. More importantly there appears to be about 5 mm of offset. Hopefully the new BB corrects this issue since the offset is set by insertion from the drive side. And if the BB bottoms out before the axle and cranks are centered then there's nothing easy to do to fix the issue.

While it's nice to have a low Q crank setup (that's where the space between pedals is smaller) it's not the end of the world. MTB's all have high Q setups and no one seems to worry too much about those. Road racer bikes have low Q setups and when in a tuck with knees in the low Q aids with rider efficiency. But a touring bike is in between.

At the risk of embarrasing the Rivendell staff I'd take the frame and cranks in and show them what their recomendation did. Hopefully they'll make it right for you before you leave.

Grand Bois

Which Rivendell model is your bike?

helpless

I located a 115mm BB, so I pulled the cranks and removed the old BB and then installed the 115mm BB. Now each crank arm clears the chain stay by ~5mm. I didn't expect so much clearance on the non-drive side(the crank hitting the chain stay), nor that the clearance for each crank would be the same. I expected ~7mm and ~3mm.

Also, if I took 4mm of clearance off both sides for the new 115mm crank so that each crank only has 1mm of clearance, then 2 x 4mm = 8mm, and 115mm - 8mm = 107mm. I don't get it. Maybe I will try installing the 107mm BB again.






I don't live near Rivendell, but I sent them the picture of the crank hitting the chain stay.

powers2b

Your crankarm or frame got bend in shipping.
Happens frequently on bikes.
Have both checked out before you 'doubt' Rivendale.
I'm sure a company that sells thousands of bikes would notice if they started installing the wrong bb on the assembly line.

Enjoy

helpless

I reinstalled the 107mm BB, and I reinstalled the non-drive side crank. It still hits the chain stay.

What do people think, should I use the 115mm BB or should I try a 110mm or 111mm BB? What's the minimum clearance for a 175mm crank?

helpless

Both the box with the components and the box with the frame were in good shape when I received them. Also, with the 115mm BB the clearance seems the same for both crank arms.


I don't think they sell thousands of bikes, and they probably don't sell many with the Sugino XD600 crank. If the frame was bent, wouldn't the rear wheel not be centered? I'll check that.

helpless

I measured the distance from the sides of the rim to the chain stays, and they seem to be equidistant.

powers2b

Sounds like you and Grant Peterson should have a little chit chat.

says Petersen. Rivendell sells just 600 bicycles a year, but they are
all hand-built with exquisite attention to detail and sell for $1,700 to $4,000.

https://www.prenhall.com/behindtheboo...merer_CH03.pdf
Page 25

Enjoy

badamsjr

I have done a lot of switch'n'swap with cranks and bottom brackets, and have found that not every combination works. If you have ~5mm clearance each side with a 115mm spindle you could get it down to ~3mm each side with a 111mm spindle IF the spindle has equal offset (the distance it sticks out from the body of the BB). That applies to the 115mm as well. Did you check the offset? What about the 107mm? I have seen variations in different BB's, so perhaps that is what happened with the 107mm? If one side has 25mm(example only) and the other 23mm, one side will be 2mm closer than the other!