Before you start another TT thread, click here.
#776
Version 7.0
FWIW, when we lived in NorCal, there was a time trial practice series consisting of 4 to 5 races per season on a Saturday morning. The TT course was an out and back 400 feet of total climbing 9.7 miles and not technical or punchy climbing. The races were timed to correspond with major sanctioned time trial events such as state and nationals as well as other time trial races.
They had aero men and women, Merckx men and women and team men and women plus tandem. In general, they got about 100 riders and many did two events - Aero and Merckx and maybe team. Those that were competing in state 40 ITT did two aero events. My wife usually did an individual woman and team women. I did individual male aero.
This was a race day so once a racer decided to do the TT, show up, set up, warmup and race, why not do a couple of TT events.
Team events are a lot of fun and compete well with mass start races. Well executed TTTs are more satisfying, IMO, than crits. After a 4 man TTT there is a lot to talk about and socialize versus an individual ITT. You have real team work and teams practice for TTT events. But yet another reason to have a simple course that is not technical or hilly.
We also had a Thursday night time trial on the same course run by a guy. He got maybe 10 racers, if he was lucky and 1/2 of them did not know how to race a time trial. We did his races when he had them.
My wife and I did a TTT yesterday and today on Fiesta but would be do a timed ITT two days back to back and pay someone a fee? NO WAY. One timed ITT a month is a lot.
And I would make it a 20km course. Most time trial racers race 20k or 40k at State championships. I will race pursuit at the track versus a “prologue” TT.
If you go the Strava idea, IMO, you need a starting protocol and a time window.
They had aero men and women, Merckx men and women and team men and women plus tandem. In general, they got about 100 riders and many did two events - Aero and Merckx and maybe team. Those that were competing in state 40 ITT did two aero events. My wife usually did an individual woman and team women. I did individual male aero.
This was a race day so once a racer decided to do the TT, show up, set up, warmup and race, why not do a couple of TT events.
Team events are a lot of fun and compete well with mass start races. Well executed TTTs are more satisfying, IMO, than crits. After a 4 man TTT there is a lot to talk about and socialize versus an individual ITT. You have real team work and teams practice for TTT events. But yet another reason to have a simple course that is not technical or hilly.
We also had a Thursday night time trial on the same course run by a guy. He got maybe 10 racers, if he was lucky and 1/2 of them did not know how to race a time trial. We did his races when he had them.
My wife and I did a TTT yesterday and today on Fiesta but would be do a timed ITT two days back to back and pay someone a fee? NO WAY. One timed ITT a month is a lot.
And I would make it a 20km course. Most time trial racers race 20k or 40k at State championships. I will race pursuit at the track versus a “prologue” TT.
If you go the Strava idea, IMO, you need a starting protocol and a time window.
#777
Newbie racer
Either way, Strava does the timing........so there's the chore of setting up the segment so that people don't accidentally "false start" the timer or have the segment grab a ton of "weeknight worlds" rides passing by.
I usually try to go pre-ride and create a segment where you have a little 200 yard "dog leg" of some kind off a side street or some feature where there is almost zero chance someone has ridden that segment before outside of a TT.
I think the easiest thing though is see if people would meetup in the other town. In town we have the arena. Almost zero traffic, wide wide lanes. Safer. Good for a beginner.
I think the ideas of different types is a bit ambitious. And perhaps confusing.
Raleigh Brewing is an easy 2 to 3 mile warmup from the arena and the route there you can take is also mostly hidden from traffic.
I did the "Arena hour" segment this year, so I can use that to go in and create as many segment distances as I want. There's already a one lap, and a 21mi segment. I'll create a 10mi, and I'll create one for 25mi......I did do 25mi the day I tried the "Arena hour" as I figured......I've gone this far, why not.
I usually try to go pre-ride and create a segment where you have a little 200 yard "dog leg" of some kind off a side street or some feature where there is almost zero chance someone has ridden that segment before outside of a TT.
I think the easiest thing though is see if people would meetup in the other town. In town we have the arena. Almost zero traffic, wide wide lanes. Safer. Good for a beginner.
I think the ideas of different types is a bit ambitious. And perhaps confusing.
Raleigh Brewing is an easy 2 to 3 mile warmup from the arena and the route there you can take is also mostly hidden from traffic.
I did the "Arena hour" segment this year, so I can use that to go in and create as many segment distances as I want. There's already a one lap, and a 21mi segment. I'll create a 10mi, and I'll create one for 25mi......I did do 25mi the day I tried the "Arena hour" as I figured......I've gone this far, why not.
#778
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Location: Sacramento, California, USA
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Hey, just seeing this. We had a local weekly TT series in Sacramento this year which was a lot of fun and a nice way to channel our racing energy during the pandemic. Basically, you need Strava, a Facebook group, and a couple cans of paint. The "Commissioner" would go out each week and lay out a course and create a segment on Strava. Someone would mark the start, finish, and any turns with paint, take a few photos, and post it to the Facebook group. Race day was Thursday and you could go anytime you wanted that day, up till 9pm so the Commissioner could tabulate the results. People would post on FB and heckle each other online.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
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#779
Newbie racer
Hey, just seeing this. We had a local weekly TT series in Sacramento this year which was a lot of fun and a nice way to channel our racing energy during the pandemic. Basically, you need Strava, a Facebook group, and a couple cans of paint. The "Commissioner" would go out each week and lay out a course and create a segment on Strava. Someone would mark the start, finish, and any turns with paint, take a few photos, and post it to the Facebook group. Race day was Thursday and you could go anytime you wanted that day, up till 9pm so the Commissioner could tabulate the results. People would post on FB and heckle each other online.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
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#780
Newbie racer
I "thought" I got a great Black Friday deal on a Nopinz/Aerocoach suit. It was. Then three days after getting it and riding it and loving it.......their CEO posts this for sale for a freaking steal on Ebay. Worn once for a photo op with the company, never ridden, my size.....
I couldn't say no. Even if keeping one to train and do club runs in and the other for races. My Bodypaint 3.3 fits me so badly in places (loose) that I'm going to sell it and keep these two without even testing. It would have creases in bad places. This thing..........whew it's nice.
I couldn't say no. Even if keeping one to train and do club runs in and the other for races. My Bodypaint 3.3 fits me so badly in places (loose) that I'm going to sell it and keep these two without even testing. It would have creases in bad places. This thing..........whew it's nice.
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#782
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There was a user here back in the day Nate552 that claimed to be able to do 40 kph on 200w in windless conditions. Pretty neat.
__________________
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
#783
Senior Member
assume a rider + TT bike setup system weight of 70 kg.
Crr of 0.004 for some smooth rolling roads
and a CdA of 0.2 (that's a really dialed position already! world-class could be a bit lower)
air density 1.25 kg/m^3
g = 10 (easy mode)
0.004*70*10*11.11 + (1/2)*0.2*1.25*11.11^3 = 203 Watts
aforementioned 200 Watts at 40 kph is about the lowest you can expect. If you are a world class pro on a world class setup you can get it lower somewhat but that's scraping the edges of marginal gains.
#784
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25 mph ~ 40 km/h -> 40/3.6 = 11.11 m/s
assume a rider + TT bike setup system weight of 70 kg.
Crr of 0.004 for some smooth rolling roads
and a CdA of 0.2 (that's a really dialed position already! world-class could be a bit lower)
air density 1.25 kg/m^3
g = 10 (easy mode)
0.004*70*10*11.11 + (1/2)*0.2*1.25*11.11^3 = 203 Watts
aforementioned 200 Watts at 40 kph is about the lowest you can expect. If you are a world class pro on a world class setup you can get it lower somewhat but that's scraping the edges of marginal gains.
assume a rider + TT bike setup system weight of 70 kg.
Crr of 0.004 for some smooth rolling roads
and a CdA of 0.2 (that's a really dialed position already! world-class could be a bit lower)
air density 1.25 kg/m^3
g = 10 (easy mode)
0.004*70*10*11.11 + (1/2)*0.2*1.25*11.11^3 = 203 Watts
aforementioned 200 Watts at 40 kph is about the lowest you can expect. If you are a world class pro on a world class setup you can get it lower somewhat but that's scraping the edges of marginal gains.
Anyway, we post so much about power, and not so much about speed from how little power, I thought it an interesting question/exercize.
#785
Newbie racer
CRR varies a lot by where you ride also. Down east is pan flat but bad pavement. The club 8.5mi TT has three little steady hills but pavement is excellent. I’m only like 1/2mph slower on the hilly route.
Also, meters. My old Stages left only had me at like 230w for 25mph. My Quarq, 245. I trust the Quarq.
Also, altitude or air density.
I have no idea my absolute CdA or power at speeds. Just test for incremental improvements. I should try.
Also, meters. My old Stages left only had me at like 230w for 25mph. My Quarq, 245. I trust the Quarq.
Also, altitude or air density.
I have no idea my absolute CdA or power at speeds. Just test for incremental improvements. I should try.
#786
Newbie racer
There was a user here back in the day Nate552 that claimed to be able to do 40 kph on 200w in windless conditions. Pretty neat.
What I find weird about the folks that are super fast on low watts is that the modern ideas behind some of the positions basically make things a "one trick pony".
In other words, that guy or gal might be silly fast at 25mph on only 200w.......but their CdA will not be that great for 28mph or 30mph.
Why?
Things like the tilted cockpit stuff with arms and hands, most of the long tail or broad tail or big body helmets, doesn't lend itself well to "high yaw" situations. High and medium yaw is what your average "Ironman finisher" will experience on an average day doing about 20 to 23mph on the bike leg of an Ironman. Medium yaw is the same if going probably 23 to 26 or 27mph. Low would be the same above 27mph.
I made a spreadsheet where I can put in the day's wind speed and direction and have it spit out an estimate of yaw angles based on rider speeds.
Back to the Nate guy doing 25mph on 200w. That's awesome, but modern idea is that probably won't work out super great closing in on 30mph. Your position's CdA can vary based upon your airspeed. Airspeed affects yaw angle, and yaw angle can alter CdA and drag.
Also, there's certain days and routes that can really make you seem faster. When I did the Charlotte Speedway TT years back, the wind that day was coming from a direction that when you should have had a headwind, the huge front bleachers were blocking it! Then the entire backstretch, they don't have the tall bleachers/grandstand blocking the wind. So the tailwind is just pushing you along! That day a LOT of people put out times at or over 25mph on some silly low power. I think I only put out like 225 to go 25mph.
So, I'd take some of this stuff with a grain of salt. And if a pro has a CdA of 0.190 at 33mph.................at 20mph that is likely probably worse. Still really "good".......but probably an order of magnitude worse than at 33+ mph. Like, going from an 0.190 to over .200.
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#788
Senior Member
I thought about this one a good bit before deciding to respond.
What I find weird about the folks that are super fast on low watts is that the modern ideas behind some of the positions basically make things a "one trick pony".
In other words, that guy or gal might be silly fast at 25mph on only 200w.......but their CdA will not be that great for 28mph or 30mph.
Why?
Things like the tilted cockpit stuff with arms and hands, most of the long tail or broad tail or big body helmets, doesn't lend itself well to "high yaw" situations. High and medium yaw is what your average "Ironman finisher" will experience on an average day doing about 20 to 23mph on the bike leg of an Ironman. Medium yaw is the same if going probably 23 to 26 or 27mph. Low would be the same above 27mph.
I made a spreadsheet where I can put in the day's wind speed and direction and have it spit out an estimate of yaw angles based on rider speeds.
Back to the Nate guy doing 25mph on 200w. That's awesome, but modern idea is that probably won't work out super great closing in on 30mph. Your position's CdA can vary based upon your airspeed. Airspeed affects yaw angle, and yaw angle can alter CdA and drag.
Also, there's certain days and routes that can really make you seem faster. When I did the Charlotte Speedway TT years back, the wind that day was coming from a direction that when you should have had a headwind, the huge front bleachers were blocking it! Then the entire backstretch, they don't have the tall bleachers/grandstand blocking the wind. So the tailwind is just pushing you along! That day a LOT of people put out times at or over 25mph on some silly low power. I think I only put out like 225 to go 25mph.
So, I'd take some of this stuff with a grain of salt. And if a pro has a CdA of 0.190 at 33mph.................at 20mph that is likely probably worse. Still really "good".......but probably an order of magnitude worse than at 33+ mph. Like, going from an 0.190 to over .200.
What I find weird about the folks that are super fast on low watts is that the modern ideas behind some of the positions basically make things a "one trick pony".
In other words, that guy or gal might be silly fast at 25mph on only 200w.......but their CdA will not be that great for 28mph or 30mph.
Why?
Things like the tilted cockpit stuff with arms and hands, most of the long tail or broad tail or big body helmets, doesn't lend itself well to "high yaw" situations. High and medium yaw is what your average "Ironman finisher" will experience on an average day doing about 20 to 23mph on the bike leg of an Ironman. Medium yaw is the same if going probably 23 to 26 or 27mph. Low would be the same above 27mph.
I made a spreadsheet where I can put in the day's wind speed and direction and have it spit out an estimate of yaw angles based on rider speeds.
Back to the Nate guy doing 25mph on 200w. That's awesome, but modern idea is that probably won't work out super great closing in on 30mph. Your position's CdA can vary based upon your airspeed. Airspeed affects yaw angle, and yaw angle can alter CdA and drag.
Also, there's certain days and routes that can really make you seem faster. When I did the Charlotte Speedway TT years back, the wind that day was coming from a direction that when you should have had a headwind, the huge front bleachers were blocking it! Then the entire backstretch, they don't have the tall bleachers/grandstand blocking the wind. So the tailwind is just pushing you along! That day a LOT of people put out times at or over 25mph on some silly low power. I think I only put out like 225 to go 25mph.
So, I'd take some of this stuff with a grain of salt. And if a pro has a CdA of 0.190 at 33mph.................at 20mph that is likely probably worse. Still really "good".......but probably an order of magnitude worse than at 33+ mph. Like, going from an 0.190 to over .200.
#789
Newbie racer
I figure if you're uphill around here, your airspeed is typically under 20mph. Meaning, it likely won't matter for squat which suit you chose. If headwind, your airspeed will still be 27mph even if you're not going 27mph. That's just how it works. People think too often in terms of "ground speed".
So if your TT looks like 75% at 27mph on flats and 12.5% under 20mph uphill and 12.5% over 30mph........that's 87.5% of your ride time spent at or above the design speed. So, if I had chosen the "slow" suit I wouldn't gain anything at that 12.5% of the time I spend over 30mph airspeed. I also wouldn't gain anything with it going under 20mph uphill.
I'm in that weird spot for those suits where I'm too quick for slow suits and too slow for fast suits to really really shine bright. I need another mph I guess. That's the plan for next year! Get into the 21:XX range for 10mi.
#790
Senior Member
Hey, just seeing this. We had a local weekly TT series in Sacramento this year which was a lot of fun and a nice way to channel our racing energy during the pandemic. Basically, you need Strava, a Facebook group, and a couple cans of paint. The "Commissioner" would go out each week and lay out a course and create a segment on Strava. Someone would mark the start, finish, and any turns with paint, take a few photos, and post it to the Facebook group. Race day was Thursday and you could go anytime you wanted that day, up till 9pm so the Commissioner could tabulate the results. People would post on FB and heckle each other online.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
A lot of the courses were on a paved canal path that everyone knows, but to mix it up, there were days where everyone had to go Merckx, hill climbs, gravel courses, and no-limit aero days. In addition to times, the Commissioner would award points for social media engagement (heckling each other on FB, basically), inventive or funny Strava titles, and just random bonus points.
Personally, it was one of the best things in my cycling life this year, especially since it was quality bonding time with my son.
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#792
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Finishing up my block today with another TT bike ride. I'm tryna do 2x/week. Before I start my next training block, I want to install the 15 degree tilt adaptors (aerocoach) and start messing with that a bit. With no imminent racing on the calendar, I've been lazy about it. I like to think of TT'ing with Continuous Improvement type ethos. I haven't implemented that quite yet, and am just riding the bike for now.
The adaptors are going to add a little bit of stack, but I think that it should be worth it. or at least interesting I'll try to do some b4/after photos.
The adaptors are going to add a little bit of stack, but I think that it should be worth it. or at least interesting I'll try to do some b4/after photos.
__________________
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
#793
Senior Member
Join Date: Nov 2015
Location: Music City, USA
Posts: 4,444
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Finishing up my block today with another TT bike ride. I'm tryna do 2x/week. Before I start my next training block, I want to install the 15 degree tilt adaptors (aerocoach) and start messing with that a bit. With no imminent racing on the calendar, I've been lazy about it. I like to think of TT'ing with Continuous Improvement type ethos. I haven't implemented that quite yet, and am just riding the bike for now.
Also got a pair of the semi-generic aerobars off Ebay for $115 last week. Similar to the PDQ brand...maybe? They're pretty awesome. Just need to dial everything in as when I rode it the other day I found myself moving forwards and backwards on the saddle quite a bit. I realized my pads, while at a similar height to my road bike bars, were actually about 4 cm further forward and I was trying to put my elbows on them, causing me to overreach significantly. I ordered a 70mm stem for that, and then the tilt adaptors were too good a deal to pass up.
The only issue is not being sure if the tilt adaptors and the aerobar spacers will work together. Hopefully they're here today and I can see.
Working on time trial stuff will be a fun way to get rolling this spring since we have no planned races at the moment.
#794
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I hope they work together... I have the same style bars from Alibaba, "HB029". We'll see soonish.
__________________
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
#795
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Are your spacers flat-edged or do they have notches/teeth? Mine have two notches or so, which it doesn't seem most others have. That's the bit that has me a little concerned. Wonder how difficult it would be to remove the notches and just have everything flush...
#796
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IIRC, I think only the bottom spacer has the notches where the allen bolts go in, and the other ones are flat/flush. I guess I'll see in the next week or two when I plan on taking it apart again to install the adapters for the high-hands position.
__________________
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste
#797
Senior Member
got it set up with these angled wedges for a high hand position: https://www.aerolabuk.com/product-page/angled-arm-rests
And i changed out the extensions to Zipp Vuka 110 extensions.
Setup works great, i just want to change out the elbow pads. I think the stock ones aren't any good and i keep sliding around on them. Looking to get some high-sided elbow pads, but they are pretty expensive for a simple bent carbon / aluminium sheet with some holes drilled in it.
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#798
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Got my spacers. They aren't the tilt blocks, they're the armrests blocks. And they didn't include the washers, so can't even really use those. Was a total waste of $25, so that's annoying.
I couldn't figure out how any type of angled spacer would work, but now I see the proper tilt block adapters have a plate that slots in that the bolts thread to, and then you attach to the bare bar? Seems pretty cool. I guess I'll abandon it for now since I don't want to spend another 130 bucks for the proper tilt block from aerocoach. May reconsider this summer.
Stem should be here today at least, so hopefully I can get it all adjusted and dialed in a bit better.
I couldn't figure out how any type of angled spacer would work, but now I see the proper tilt block adapters have a plate that slots in that the bolts thread to, and then you attach to the bare bar? Seems pretty cool. I guess I'll abandon it for now since I don't want to spend another 130 bucks for the proper tilt block from aerocoach. May reconsider this summer.
Stem should be here today at least, so hopefully I can get it all adjusted and dialed in a bit better.
#799
Newbie racer
I made my own alloy 15 deg shims recently out of aluminum. I know since it isn't store bought that means it isn't world record trackie Doge approved. Whatever. My 3d printed Aerocoach ones disintegrated. The key with the non-threaded shims is to have a bevel washer for the bolts to contact with. That way you don't need the fancy threaded style shims.
My favorite upgrade has been the Aerocoach wing arm rests. The high sides are a godsend on rough roads and big bumps, staying locked in. You just have to be careful rising out of them for a corner or hill to not scratch yourself on the sides.
Several pros in 2020 ran those wing arm rests as "unbranded" by ripping the stickers off.
My favorite upgrade has been the Aerocoach wing arm rests. The high sides are a godsend on rough roads and big bumps, staying locked in. You just have to be careful rising out of them for a corner or hill to not scratch yourself on the sides.
Several pros in 2020 ran those wing arm rests as "unbranded" by ripping the stickers off.
#800
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I made my own alloy 15 deg shims recently out of aluminum. I know since it isn't store bought that means it isn't world record trackie Doge approved. Whatever. My 3d printed Aerocoach ones disintegrated. The key with the non-threaded shims is to have a bevel washer for the bolts to contact with. That way you don't need the fancy threaded style shims.
.
.
Both the bottom where the bolt enters the basebar and the arm rest are strictly a hole with no slots to change the bolt angle.
Not sure if that makes sense, but here's what mine looked like when I tried just to see if it was something I could work out. There's no way to change the angle of the bolts, so no shims would seem like they'd work.
Last edited by rubiksoval; 01-20-21 at 11:40 AM.