Always wanted a belt drive, but never had a chance to realize it. Cool to see this modernity come to such a classic frame.
Silver King Unchained: BELT DRIVE....What a ride~!
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Day 4 Update on SKU: Parts is Parts
Remember the Wendy's old chicken sandwich ad? Maybe this will refresh your memory...
Well, I can say for this Silver King Unchained build, parts is definitely not PARTS. And knowing that I had to be sure that things were going to work before I went ahead and bought some 'SKU build specific' parts, I had to dismantle
( read: wrestle with, soak he H-E-double toothpicks out with PB Blaster, and resort to non-traditional extraction methods) last Fall before I went ahead any further. I knew I would have fun using the Trek Belt drive crank ring, cog ring, and belt tension device on another build if it didn't work out. And I had the belt on order that would fit the system as well; all in for only about $75 at the time.
But, if for some reason I couldn't get the bottom bracket and cranks, and the fork and headset out of the SK frame, then I would bag the idea and move on to another frame at another time.
Here are some photos from my experience wrestling with those rusted solid, 76 yr old parts, minus the swearing.
I managed to eventually, over the coarse of a couple weeks of off and on soaking with PB Blaster, and as gentle persuasion as I could muster so as not to damage the cast duralium frame, get those parts removed.
One turn of the saddle on the seat post to see if I could pull it out, after MANY applications of PB Blaster, and I snapped the very short snub of seatpost off right at the top of the seat tube.
This is now here today, I attempted to pull on the post and see if it had loosened up over the winter, if the freezing and thawing of the BACK40 had worked it's magic. No dice. There wasn't much to get a hold of as the post sheared off right at the top. I have been using a drill bit to gradually remove what is left of the post inside. Have a couple ideas about how I might approach a 'seat post' as it were. Might have a rat rod modification on my hands for sure. Already made two trips to my local Ace Hardware. My staff friends just nod and smile. They know it's bike building season again....
RaT oN~!
Remember the Wendy's old chicken sandwich ad? Maybe this will refresh your memory...
Well, I can say for this Silver King Unchained build, parts is definitely not PARTS. And knowing that I had to be sure that things were going to work before I went ahead and bought some 'SKU build specific' parts, I had to dismantle
( read: wrestle with, soak he H-E-double toothpicks out with PB Blaster, and resort to non-traditional extraction methods) last Fall before I went ahead any further. I knew I would have fun using the Trek Belt drive crank ring, cog ring, and belt tension device on another build if it didn't work out. And I had the belt on order that would fit the system as well; all in for only about $75 at the time.
But, if for some reason I couldn't get the bottom bracket and cranks, and the fork and headset out of the SK frame, then I would bag the idea and move on to another frame at another time.
Here are some photos from my experience wrestling with those rusted solid, 76 yr old parts, minus the swearing.
I managed to eventually, over the coarse of a couple weeks of off and on soaking with PB Blaster, and as gentle persuasion as I could muster so as not to damage the cast duralium frame, get those parts removed.
One turn of the saddle on the seat post to see if I could pull it out, after MANY applications of PB Blaster, and I snapped the very short snub of seatpost off right at the top of the seat tube.
This is now here today, I attempted to pull on the post and see if it had loosened up over the winter, if the freezing and thawing of the BACK40 had worked it's magic. No dice. There wasn't much to get a hold of as the post sheared off right at the top. I have been using a drill bit to gradually remove what is left of the post inside. Have a couple ideas about how I might approach a 'seat post' as it were. Might have a rat rod modification on my hands for sure. Already made two trips to my local Ace Hardware. My staff friends just nod and smile. They know it's bike building season again....
RaT oN~!
Day 5 Update
I've got some other time consuming events / music gigs / family stuff coming up this summer, so I'm moving right along in typical OJ speed on this build!
I removed the wheels from the Felt Flying Machine, as I've decided those are the only parts I will be using from this bike. I am happy to report that the Felt will be on it's way to another forum member, @rat krate orange , so he can enjoy all of it's goodness. Thanks 'razin!
As @The Renaissance Man mentioned in an earlier post, this cast duralium aluminum alloy , like most aluminums, doesn't bend and flex like steel. So there won't be any spreading of the rear stays to wedge a hub in. And, I need a specific cassette style hub, with the appropriate hub body and lock ring to mount the belt drive cog to. This is a 'freewheeling hub', designed to be used with a rim brake style wheel. Which my Felt wheels are not. So, the SKU will have a front brake only, which for a cruising style bike is usually sufficient, i.e. coaster brake. More on that later....
So at work on Monday, I had a tech chat with my good friend and our Service Manager, Todd, about how we should approach the hub / wheel building issues. He will be building these wheels for me, as he has access to the right tools and is an excellent wheel builder. We have a spoke cutting machine in the shop too, so he can custom cut the spokes for each wheel after he gets the new hubs in hand. I ordered the appropriate hubs from our distributor that night, and they are due in today. Over the years I have purchased many parts through JBI.bike, which is a wholesaler that serves the entire United States, with 11 warehouse locations to ship from throughout the country. Our shop happens to be only 10 miles from the headquarters and warehouse in the Twin Cities.
Here are the two hubs I have ordered. I pulled the spokes and hubs from the Felt rims before work yesterday and Todd has them in his hands, with a work order to get them built this coming Monday.
If you notice, the front hub is set up for a 6 bolt disc brake. Yup. The SKU is going to have a disc brake in the front!
As you can see, the rear OLD hub spacing is 110mm, so this should slip right in to the horizontal dropouts on the SKU with out any flexing of the frame.
Really excited to see these new wheels built up! These are by far the nicest and most specialized hubs I have ever used on a build. And with the black spokes we picked out, they should look killer!
RaT oN~!
I've got some other time consuming events / music gigs / family stuff coming up this summer, so I'm moving right along in typical OJ speed on this build!
I removed the wheels from the Felt Flying Machine, as I've decided those are the only parts I will be using from this bike. I am happy to report that the Felt will be on it's way to another forum member, @rat krate orange , so he can enjoy all of it's goodness. Thanks 'razin!
As @The Renaissance Man mentioned in an earlier post, this cast duralium aluminum alloy , like most aluminums, doesn't bend and flex like steel. So there won't be any spreading of the rear stays to wedge a hub in. And, I need a specific cassette style hub, with the appropriate hub body and lock ring to mount the belt drive cog to. This is a 'freewheeling hub', designed to be used with a rim brake style wheel. Which my Felt wheels are not. So, the SKU will have a front brake only, which for a cruising style bike is usually sufficient, i.e. coaster brake. More on that later....
So at work on Monday, I had a tech chat with my good friend and our Service Manager, Todd, about how we should approach the hub / wheel building issues. He will be building these wheels for me, as he has access to the right tools and is an excellent wheel builder. We have a spoke cutting machine in the shop too, so he can custom cut the spokes for each wheel after he gets the new hubs in hand. I ordered the appropriate hubs from our distributor that night, and they are due in today. Over the years I have purchased many parts through JBI.bike, which is a wholesaler that serves the entire United States, with 11 warehouse locations to ship from throughout the country. Our shop happens to be only 10 miles from the headquarters and warehouse in the Twin Cities.
Here are the two hubs I have ordered. I pulled the spokes and hubs from the Felt rims before work yesterday and Todd has them in his hands, with a work order to get them built this coming Monday.
If you notice, the front hub is set up for a 6 bolt disc brake. Yup. The SKU is going to have a disc brake in the front!
As you can see, the rear OLD hub spacing is 110mm, so this should slip right in to the horizontal dropouts on the SKU with out any flexing of the frame.
Really excited to see these new wheels built up! These are by far the nicest and most specialized hubs I have ever used on a build. And with the black spokes we picked out, they should look killer!
RaT oN~!
The Renaissance Man
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I'm assuming that you have a quill seat post. You may have to drive the wedge down the same way you would loosen a quill stem inside of a steer tube.
The wedge is not lodged in the seat tube, I probed with a long rod all the way to the BB, nothing but a hollow shell of a seat post. I will implement some kind of quill system for mounting a seat. Couple ideas floating around right now.
I did some research into this a few years back when I had the Silver King Wingbar frame. @pvwacko pointed me to the gates calculator since he has done a few belt drive customs over the years. I remember him mentioning that you need to be precise with the belt length since you can't really remove a link like a chain.
https://www.gatescarbondrive.com/products/tools
I know that a few belt drive Silver Kings have been built over the years, but I don't believe any were documented here on RRB. This is gonna be cool to see.
Also, along the lines of TRMs comments regarding hub spacing, you'll want to watch out for the bolt/nut that attaches the seat and chain stays together. It sorta takes up some of the space where the cog/chain/belt are. I had to work around that last year with my nexus7 hub on HEXtreme. I believe I used shorter bolts and thinner nuts to gain clearance from the cog and chain.
You may be able to use a hacksaw blade inside the broken seatpost to saw some breaks into the post to make it be able to collapse on itself and remove it piece by piece.
The problem of having the steel seatpost frozen in these duralium seat tubes is not unusual. I believe part of the issue is the corrosion that can happen between disimilar metals. I don't really know the solution, but giving you something else to search on.
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You can try applying some heat to the aluminium which can help brake the fusion with the steel post. A small gas torch is all you need.
Thanks to Royal Ichthus (play on his name.... 
) and JA331 for your suggestions on the post removal in SKU!
Day 6 Update on Silver King Unchained
I have more post removal scheduled for today. Most Springs by this time, we would be making a trip up to our camp in Northern Wisconsin to open things up. But the ice is just finally moving out of the lake, so no reason to jump the gun. And we finally had a nice couple days in the 60's here, so yard work and just plain hanging out in the sun were on the agenda!
I'm working on Mondays and Wednesdays at the bike shop this year, gets me out of the house and we have a nice tight nucleus of 5 guys on staff that have been there 5 years or longer, so that's kind of my 'second family' for the summer. Yesterday the hubs came in, and a box of raw spokes that will be cut to length to accommodate the two different hubs, and the two different rim sizes. The rear rim on the SKU is a 24" and the front is a 26". The hub flanges are pretty similar, and I unwrapped the hubs when they arrived yesterday late afternoon and took a couple shots in the late day sun of the BACK40.
The first one is the front hub. These are both bolt on hubs, so they will fit the vintage vibe well. They have 3/8" axles, but I'm planning a modern fork for this bike, so it should fit the fork drops fine. You can see the disc brake 6 bolt mount on the left side of the hub here.
This one below is the rear hub. It's a bmx style cassette hub, which has a shorter body than a multi-geared bike would need. And a special kind of lock ring to hold the cog in place. Should be enough room on there for the belt drive gear to slide on and then turn the lock ring on to hold it in place. The bearings in both these hubs are sealed. Really smooooooth!
Another part that came in last night was my American BB to 3 piece crank conversion bottom bracket kit. This has cups that fit the diameter of the American BB that we find on most all of our pre - 1970's or so bikes, and still common on most 1 piece crank bikes today.
Since I will have a crank ring that needs to be mounted to a 'spider' on a 130 BCD crank arm, I needed a 3 piece crank. Nothing fancy, just a traditional square tapered spindle and caged bearings for the cups.
It's a 122 mm long spindle, which will hopefully work well with the relatively narrow rear end on this bike. Lining up the 'belt line' will be crucial in having a smooth running drivetrain.
Can't wait to see my built wheels on Monday! Hopefully I will have the seat tube reamed and making progress on a seat post idea by that time.
RaT oN~!
) and JA331 for your suggestions on the post removal in SKU! Day 6 Update on Silver King Unchained
I have more post removal scheduled for today. Most Springs by this time, we would be making a trip up to our camp in Northern Wisconsin to open things up. But the ice is just finally moving out of the lake, so no reason to jump the gun. And we finally had a nice couple days in the 60's here, so yard work and just plain hanging out in the sun were on the agenda!
I'm working on Mondays and Wednesdays at the bike shop this year, gets me out of the house and we have a nice tight nucleus of 5 guys on staff that have been there 5 years or longer, so that's kind of my 'second family' for the summer. Yesterday the hubs came in, and a box of raw spokes that will be cut to length to accommodate the two different hubs, and the two different rim sizes. The rear rim on the SKU is a 24" and the front is a 26". The hub flanges are pretty similar, and I unwrapped the hubs when they arrived yesterday late afternoon and took a couple shots in the late day sun of the BACK40.
The first one is the front hub. These are both bolt on hubs, so they will fit the vintage vibe well. They have 3/8" axles, but I'm planning a modern fork for this bike, so it should fit the fork drops fine. You can see the disc brake 6 bolt mount on the left side of the hub here.
This one below is the rear hub. It's a bmx style cassette hub, which has a shorter body than a multi-geared bike would need. And a special kind of lock ring to hold the cog in place. Should be enough room on there for the belt drive gear to slide on and then turn the lock ring on to hold it in place. The bearings in both these hubs are sealed. Really smooooooth!
Another part that came in last night was my American BB to 3 piece crank conversion bottom bracket kit. This has cups that fit the diameter of the American BB that we find on most all of our pre - 1970's or so bikes, and still common on most 1 piece crank bikes today.
Since I will have a crank ring that needs to be mounted to a 'spider' on a 130 BCD crank arm, I needed a 3 piece crank. Nothing fancy, just a traditional square tapered spindle and caged bearings for the cups.
It's a 122 mm long spindle, which will hopefully work well with the relatively narrow rear end on this bike. Lining up the 'belt line' will be crucial in having a smooth running drivetrain.
Can't wait to see my built wheels on Monday! Hopefully I will have the seat tube reamed and making progress on a seat post idea by that time.
RaT oN~!
The Renaissance Man
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I would try to keep the original bearing cups in place on the BB if possible. I think the size may be specific to the aluminum frame. If it doesn't work with the old cups, maybe the ball bearings could be replaced to get it to work. Just thoughts off of the top of my head, it may not be a problem.
Day 6.5 Update. Special live update, from the BACK40!
RaT oN~!
RaT oN~!
Cups wotk with bearings that work with BB spindle that works with....you get the idea.
I will be very surprized , and dismayed, if these new American BB cups don't fit this American made frame from the '30s.
It wasn't like I would lose sleep over it or anything, but since it's the perfect Spring evening,I wentured out to the BACK40 and tried the cups in the SKU BB. Fit like a glove, like bread and butter,@The Renaissance Man !
N'ght all.
N'ght all.
The Renaissance Man
__CERTIFIED DIVER__ (Open Water & Open Dumpster)
Staff member
Moderator
Pro Member
Nice!
Nothing comes easy on these Silver King frames. The bearing cups are unique. The rim part that shows is very thin and narrow compared to others. You might have spacing issues with those wider lipped cups you have installed. Good luck!
I'm using a 3 piece bottom bracket conversion kit, the BB spindle is 122 mm long. I measured the BB width and it is dang close to the standard 68 mm wide. 66.11 mm, to be exact. This 3 piece kit is designed for a 68 mm wide BB.
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How durable are these frames? A friend had one in high school. The frame broke. His father took it to a machine shop for repairs but it broke again. Granted late 60s aluminum repair techniques were primitive. He was a big very strong guy, all state footballer. He and I did a lot of cross country skiing and he broke 2 - 3 fiberglass or cane poles each season double poling. He finally went to aluminum poles. I think he actually folded an aluminum pole. So upon reflection, it’s only natural that he broke the frame.
Day 7 Late Day Update
Spent the day in my hometown with my near-90 mom to celebrate Mother's Day weekend. We picked up a couple potted flowers and ate lunch at a favorite cafe, that she doesn't get to often, anymore. Got home in time to enjoy our last evening of sunshine for the next few days, the way the weather sounds.
Slapped the BB conversion kit for a 3 piece crank into the cups I had pressed in to the SKU frame last night.
This oughta quell the naysayers.
RaT oN~!
Spent the day in my hometown with my near-90 mom to celebrate Mother's Day weekend. We picked up a couple potted flowers and ate lunch at a favorite cafe, that she doesn't get to often, anymore. Got home in time to enjoy our last evening of sunshine for the next few days, the way the weather sounds.
Slapped the BB conversion kit for a 3 piece crank into the cups I had pressed in to the SKU frame last night.
This oughta quell the naysayers.
RaT oN~!
