My DIY builds: GMAC, BBSHD, 9C RH212, CYC Photon, ToSeven DM01

I was able to test fit a 27.5x2.6 smart sam on a 24mm inner width rim/wheel. Definately not the best rim in actual use though but all i had lying around. The tire measured only 2.3 mounted on this rim. A true 2.6 tire would be a really close fit with the wheel all the way forward in the dropout.

Luckily being a horizontal dropout, you can just move the wheel back. Surly sell monkey nuts to make alignment easy.
surly-monkey-nuts-v3.jpg

With this nut, its apparent I could have a much bigger tire as the 2016 redesigned troll can take a 26x3.0 tire so 27.5x2.6 or even 27.5x2.8 tires are in my future. The cantilever brake mounts do get in the way but 1 minute with a dremel and they are gone.

Forgot to mention, I bought a second torque arm from grin so I will make a nicer cleaner torque arm mount.

The GMAC moto does push the rear brake rotor out as far as the spec probably allows. The caliber was at the limit of in/out adjustment so a minute with a file on the caliber bolt holes and the disc is now centered between the pads.
 
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I put the smartsam 27.5x2.6 on a 35mm inner width rim and it only measures 2.42 so it will likely work without the monkeynut mentioned in the previous post
 
Well, Im guessing the drive side crankarm is toast as even when the crankarm bolt is torqued down to 390inlbs, it loosens up. It took 60 miles before it started making noise and sure enough the bolt was loose.

I used square taper BB and cranks for over 10 years back in the day and never had this issue. I did have an old suntour crank get so used that the tapper got enlarged so that the bolt would bottom out before the crank was tight enough but that was over 3 years of hard offroad use and constant removal/mounting as I wore BBs out alot in those days due to excessive bike washing getting dirt in the BB. Even the 'known to be soft' bafang crankarms I used for my for my TSDZ2 to get a lower q factor held up fine (at least until the TSDZ2 bearings became junk).

Im guessing the extra paint or powder coating on the inside of the square taper hampered me getting them good and tight

The miranda 0 qfactor cranks sold with the erider kit dont seem to be easily available in the US so I just decided to order another torque sensor from grin. Probably not a bad spare part to have anyway. Supposedly they are a good part as they are used on alot of bikes. Might order a spare set from england although Im still researching other options.

I also noticed that the chainring had a bit of runout (inside/outside wobble). I thought I had fixed this earlier but Im guessing I didnt mount the spider the same way. While it could be a machining issue, the easiest answer would just be uneven powdercoat/paint.

Pretty sure Im going to remove the powder coat or paint on the new spider just to be safe.

So new order from grin for the spare erider torque sensor and a set of spokes for a 27.5 wheel if I decide to use those wheels on this frame.

One thing to check for are the bottom bracket shell faces, which typically need to be cleaned up on new frames (from paint and some aren't square :confused:). Paying a LBS with the proper tool is well worth it:


@AHicks worth considering too.
 
One thing to check for are the bottom bracket shell faces, which typically need to be cleaned up on new frames (from paint and some aren't square :confused:). Paying a LBS with the proper tool is well worth it:


@AHicks worth considering too.
What would the advantage be if your BB bearings spin fine? Of the 5 bikes I have built from a frameset, none have needed this. I understand the need, I just havnt needed it.

FWIW, I have been subscribed to Hambini on youtube for awhile (the youtube BB misalignment guru)

Surly recommends using a boxcutter to get the paint off mating surfaces, My surly troll didnt require this
 
The GMAC kit looks to be of high quality and would be a good fit to the host bike I’m considering to use for a home build project
Anyone know if Grin still ship their kits internationally (i.e. Australia)
I have emailed them directly on several occasions but they never reply
 
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"We will gladly welcome orders from pretty much anywhere in the world. The map below shows where some of our recent customers ordered from; all over the USA, Canada, Europe, Australia/NZ, and even South Africa and Korea. Interest in ebikes is poised to be a global phenomenon but hasn't caught on in many places, and if you can't find a local source for your parts yet we'll be glad to help you out."
Thanks Timpo
I saw that page but didn’t know if it was still relevant given things have gone crazy in this COVID age, hence my reaching out to them
However I’m not comfortable placing an order until I get some acknowledgment of my enquiry
 
In a last ditch effort to fix my drivetrain side loosening crankarm problem, I decided to try blue 242 loctite. I see lots of pros/cons on its use for crankarm bolts but figured what the heck. After 200 miles I had planned on reporting success tonight.

Wasnt going to be, about 12 miles from home the left pedal felt really weird and I looked down and could see it was REALLY loose. Tightened it several times and it got to the point that I couldnt even go a mile. At one point while tightening, it suddenly got easier to tighten (Im guessing the crankarm split). At that point, I couldnt use the crank at all without loosening and focused all my weight on the right side. The left side crankarm never had any issue up to this point.

Throttle saved me today, only way to get home. That being said, neither of my brose mid drives would fail this way as they are not using the obsolete square taper BB design. I hated the ride home using the throttle only.

Lucikly I ordered a second erider BB with crankarms so I will try those tomorrow. I am also going to try a set of crankarms for a shimano 6100 mid drive which look compatible.

So I decided to come home and replace the rear tire and true rear wheel on my iZIP moda E3 with 4k miles. Rim had fractures in several spots focusing around spoke holes but also further towards the outside of the rim like possible fractures from less than perfect hopping up curbs which are steep out here in CO.

I bought a park truing stand/dishing gauge and spoke tension gauge in anticipation of going to wider 27.5 wheels on the GMAC build. Looks like this was a wise choice as trying to find a quality 27.5 built rear-wheel at a less than $500 price seems pretty hard. New spokes, nipples and a WTB bikepacking rim cost about $140 for one wheel (I bought parts for 2 wheels though).

So 2 ebikes down, glad I have 2 more
 
You might be able to convert to disc brakes, I did it on my Zaskar about 10 years ago.

For the front, just buy a new fork with disk mounts. When my zaskar wasnt my primary MTB anymore I put on a rigid disc fork. I bought a suspension fork awhile back (rockshox reba) that had both canti and disc brake mounts.

For the rear, you could use the A2Z adapter. I used this for over 9 years on my Zaskar. Its big, bulky and fiddly but works
View attachment 68199

I knew this could cause problems with a hub motor so I recently got an adapter specifically for the Zaskar
View attachment 68200

I still might have fitment issues, we will have to see
Hi,
Is this adapter custom-made? I'm interested in exactly this thing as I have non-disc frame too. The A2Z looks tempting - I have a rear hub conversion on an aluminium frame and I use the eyelets to mount torque arms. How is yours working? If it's a viable option, I may see about getting one made up that also functions as a torque arm. Yes, I could get a new frame, but I really like this one.
 
Hi,
Is this adapter custom-made? I'm interested in exactly this thing as I have non-disc frame too. The A2Z looks tempting - I have a rear hub conversion on an aluminium frame and I use the eyelets to mount torque arms. How is yours working? If it's a viable option, I may see about getting one made up that also functions as a torque arm. Yes, I could get a new frame, but I really like this one.
I originally had the a2z adapter. It was pretty commonly used back when I bought it in 2007ish, Its very fiddly to get setup/aligned but I used it for 13 years. It only has a hole sized for a QR skewer so you would have to drill it out.

Depending on your skills and patience, you could likely even use it as a torque arm.

I felt it would be too much work so I used the other adapter that I found on ebay (the black adapter on the silver frame). That design while frame specific was soooo much nicer and simpler. In the end, it interfered with the GMAC torquearm
 
I originally had the a2z adapter. It was pretty commonly used back when I bought it in 2007ish, Its very fiddly to get setup/aligned but I used it for 13 years. It only has a hole sized for a QR skewer so you would have to drill it out.

Depending on your skills and patience, you could likely even use it as a torque arm.

I felt it would be too much work so I used the other adapter that I found on ebay (the black adapter on the silver frame). That design while frame specific was soooo much nicer and simpler. In the end, it interfered with the GMAC torquearm
Thanks for the info - very useful. On the Zaskar, did you have to drill the mounting holes to the dropout plate? The A2Z looks quite secure with the four bolts - I'm a bit unsure about whether two eyelets would hold a caliper well? Mind you, they're good enough for a torque arm so in assuming it wouldn't have too much issue. This is the torque arm I'm using. The way the dropout space was cut into it means I have to mount it in a weird way which covers up the second eyelet. The mudguard struts are quite far out which pinches the mudguard itself up top. I'm looking to devise an all-in-one solution.
If I have a plate cut, it would be secured in the two eyelets above the dropout, plus the nut on the axle itself - should be fine right?!
Sorry for the threadjack...
 

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So Im at about 700 miles now so its time for some updates.

Overall absolutely loving the bike. Definately my most powerful bike and so far has taken everything I have thrown at it. I mostly ride it at 1.5x assist averaging about 200human watts although the extra power is nice when required like today when a cold front blew in and I just wanted to get home as fast as possible using 5x assist.

Ironically, Im not much of a throttle guy but find myself using it alot to make downhills faster. No waiting on gravity to speed up :cool:

Finally got all the parts/tools to build my own wheels and glad I did as I noticed rear wheel rim stress cracks on 2 of my other ebikes so at this point, the tools have pretty much paid for themselves (assuming $100 for a wheel build).

So upgraded wheels from 26inch to 27.5 inch (it was always the plan)

Going from 26x2.35 to 27.5x2.6 smartsams was quite a noticable change in ride quality(both at 30psi although I will ride the 2.6 at 25psi eventually). The tire clearance was just about perfect and didnt require the 'monkey nuts' shown in post #84. There was a 3/4 inch bb height increase but thats fine since the bb height was pretty low with the 26inch tires at 11.8inches.

Put on some new miranda crankarms since the previous set became toast due to loosening. About 6 rides on these new crankarms and they seem to require tightening after every ride. I initially marked the bolt/crankarm with paint and have had to increase them about 3/4 of a turn at this point (note that the bolts dont unscrew). Im torquing them to 35ftlbs which on the high side for a square taper crankarm bolt.

Also bought a set of bafang bbs02/bbshd crankarms (super cheap) and a set of shimano FC-E600 crankarms to try in case the miranda cranks dont work out. All these crankarms have about the same q factor.

So, all is perfect except for loosening crankarms. Hopefully I can get this working soon as well.

Ordered a second throttle to play with regen and ordered a battery powered light that will connect to the CA easily.
https://ebikes.ca/shop/electric-bicycle-parts/lights/roxim-x4-ebike-light.html

For the price, the SPL-01 is likely a better light but I dont need a primary light that bright(I have several 850 lumen offroad lights in my camelback) and wasnt sure if the daytime running leds were always on (sometimes I want total stealth)
https://ebikes.ca/shop/electric-bicycle-parts/lights/spl-01-1900-lumen-ebike-light.html
 
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Awesome thread, just discovered it tonight, just a day after I started gravitating toward a Surly bike for a DIY build, and also a former Juiced CCS owner. But you have 100x the wrenching skills I do :).

I was leaning toward the Bridge Club even without the motor, because I really want a bike that can run small diameter plus tires. I had 27.5" x2.35" (which have since been discontinued 😱) on my hybrid bike and it was glorious, the terrible pavements around me ceased to matter.

I only do road riding, and on my Juiced I got in the habit of braking less and coasting more, it sounds like the regen is more hassle than it's worth.

Anyhow, I probably won't make any moves until at least late Spring, Surlys are sold out and I'm still thinking about the Shakti Zen and Ride1Up Prodigy (Brose rigid class 3 hybrid).
 
Awesome thread, just discovered it tonight, just a day after I started gravitating toward a Surly bike for a DIY build, and also a former Juiced CCS owner. But you have 100x the wrenching skills I do :).

I was leaning toward the Bridge Club even without the motor, because I really want a bike that can run small diameter plus tires. I had 27.5" x2.35" (which have since been discontinued 😱) on my hybrid bike and it was glorious, the terrible pavements around me ceased to matter.

I only do road riding, and on my Juiced I got in the habit of braking less and coasting more, it sounds like the regen is more hassle than it's worth.

Anyhow, I probably won't make any moves until at least late Spring, Surlys are sold out and I'm still thinking about the Shakti Zen and Ride1Up Prodigy (Brose rigid class 3 hybrid).
IMHO, The Surly Bridge Club is a great bike and probably better than the Troll for a rear hub motor.

I used the Troll due to COVIDs limited supply, I had to go with the troll (which turned out to be a good thing as I got it in a large as it was all could find and it was the best size for me, my first choice would have been a medium). The troll (and any surly which uses the same rear dropout config) can be really finicky on what hub motors to use(only the GMAC will work without alot of mods). The only potential issue with the bridge club is fitting a 1x chainring large enough. Both the Troll ang Ogre can be fit with a 42t 1x mtn chainring. To go this big on the bridge club would require spacing the chainring further out which might limit using the lower rear cogs (not a big deal for me as long as I just get a cassette with cogs bigger than I need).

Surly Bridge Clubs are showing up these days as complete bikes, unfortunately they all seem to be available in red.

I will likely buy a bridge club when I can find one in black and move this build to that frame and use the troll either without a motor, or try a BBSHD/phaserunner/CA3 combo.

Sure hope the Shakti Zen works out. I love the design(especially the thru axle rear hub motor), while I prefer mid-drives, hub drives are actually better for many of my uses (<10% grade and higher speeds). I would like to own one

Also looking forward to see how the Ride1Up Prodigy works out. I basically have the same bike (2019 iZip Moda E3, 28mph, Brose, rigid). I got it at a closeout price of $2400. Nice well rounded bike. It was my preferred 28mph rig till this DIY build.
 
IMHO, The Surly Bridge Club is a great bike and probably better than the Troll for a rear hub motor.

I used the Troll due to COVIDs limited supply, I had to go with the troll (which turned out to be a good thing as I got it in a large as it was all could find and it was the best size for me, my first choice would have been a medium). The troll (and any surly which uses the same rear dropout config) can be really finicky on what hub motors to use(only the GMAC will work without alot of mods). The only potential issue with the bridge club is fitting a 1x chainring large enough. Both the Troll ang Ogre can be fit with a 42t 1x mtn chainring. To go this big on the bridge club would require spacing the chainring further out which might limit using the lower rear cogs (not a big deal for me as long as I just get a cassette with cogs bigger than I need).

Surly Bridge Clubs are showing up these days as complete bikes, unfortunately they all seem to be available in red.

I will likely buy a bridge club when I can find one in black and move this build to that frame and use the troll either without a motor, or try a BBSHD/phaserunner/CA3 combo.

Sure hope the Shakti Zen works out. I love the design(especially the thru axle rear hub motor), while I prefer mid-drives, hub drives are actually better for many of my uses (<10% grade and higher speeds). I would like to own one

Also looking forward to see how the Ride1Up Prodigy works out. I basically have the same bike (2019 iZip Moda E3, 28mph, Brose, rigid). I got it at a closeout price of $2400. Nice well rounded bike. It was my preferred 28mph rig till this DIY build.

You have put in a great deal of attention and care to select the components for your bike.
If you like the torque sensor on your bike, you will love the Zen Shakti because the sensor on the Shakti is even more refined.
E-bikes of Colorado store is on our radar and we will contact them as soon as we go into full-scale production and you should be able to test one there.
 
I just passed 1k miles on this build and I still absolutely love this bike and am glad I built it. While it can output up to 1500W and around 36mph, Im happy just pedaling it at 1.5 to 2.0 assist while I output 150 to 200 watts human watts Not much else to say here so I will just address certain areas

Cycle Analyst 3
Sure its big, bulky and downright ugly but functionally its perfect for an ebike unless you just dont care about all the options and programmability it provides. Im not sure how I would live without it these days. One of the most used functions is the Wh used. This is so much more accurate than simple voltage only capacity indicators although I have figured out how to read those accurately as well. Also a big fan of the presets (up to 3). I have one preset that is basically a US legal class 1 ebike (750W, 20mph). The second preset is used as 1000W PAS only (no torque sensor) with no speed limit. I use this preset for playing around with all the PAS options as I want to do another 52V DIY surly ebike build with a CA3, BBSHD and phaserunner. This preset is also fun for really low effort rides (ghost pedaling) where I prefer the PAS assist as opposed to using the throttle. I have the PAS setup to be power assist based (each assist level is a set amount of power). I also am using a cadence based power increasing/decreasing feature which I like. Basically after cadence of 50rpm, you can increase or decrease power based on rpm. I have found settings that I can actually live with although I still prefer torque sensing. The 3rd preset is 30amp limited(1200W just before 42V cutoff) torque sensing and no speed limit and where I ride 95% of the time.

GMAC 10t motor
Its a beast...nuff said. Without going into all the details which have been outlined before, its likely the only hub motor which would work on the surly troll frame without custom machined adapters/spacers. Havent run it in the summer yet but it usually runs around 61degrees C running 300-500W although I did get it up to 85C going up a 4-6% grade for a mile or so bucking a 20-30mph headwind doing around 25mph and about 1500W. The CA will start limiting current at 90C.

Phaserunner
This controller was overkill for this build as a baserunner would have suited me fine. That being said, there is more upgradability with this controller (like 72v).

Erider Torque Sensing BB
The main reason I even considered this build. Not as responsive as my Brose bikes but good enough for the intended use of this bike as pedal feedback isnt as important (to me) at higher speeds. Pedal feel is about as good as a DIY TSDZ2 I ran back in 2018 with opensource software. I have had the unit stop working once while riding thru a few puddles which got the bike quite wet (throttle got me home). I am running the cable from the BB to the CA under the downtube so its connector which is just in front of the BB is getting splashed by the front tire. Just bought some waterproof heatshrink to cover this connector that I will install soon.

Miranda Cranks
As noted before, the first set I just installed like I have all other square taper BB cranks over the years (pretty tight). After a few hundred miles the crankarms came loose and were destroyed (throttle got me home). I bought a second set and torqued them to 35ft-lbs (on the high side of the torque spec). I retorqued them for 10 rides, each time marking the position of the bolt with paint. Overall, the bolt was tightened ½ additional turn overall. This was done at around 400 miles so no problems for 600 miles. I also bought a set of low offset/qfactor bafang BBSxx and Shimano 6100 crankarms to have as backups.

2020 Deore brakes (2 piston)
I mention these brakes because most people would not recommend two piston calibers on a bike this powerful. I got the 2020 2 piston version at ½ price. They added 4 pistons for 2021 but at twice the price ($190). The surly frame is limited to a 160mm rotor in the rear so putting a quad piston in the back seemed silly. That being said, even with the stock resin pads, I have had no braking issues although I will eventually use a better pad compound.

Roxim X4 ebike light
Bought thru Grin, I wanted a light around 400 lumen with good cutoff so as to not blind pedestrians on many trails I encounter at night. I always run with 4 niterider lumina 850 lights in my backpack so I can supplement lights as needed. This light is about perfect for me and the cutoff works well and I have noticed people not shielding their eyes like they do with the lumina 850s even at 200 lumen. This light plugs into a power plug supplied by the CA. The SPL-01 grin sells is likely a better light for the price at 1900Lumen but I didnt want that on this bike. Only issue if if the light is switched on with the CA already on, it will reset the CA and trip settings (distance etc…). If I want to turn on the light, I turn off the CA, toggle the X4 switch, then turn on the CA again. Turning the light off has no issues.

Orign8 Strongbow Handlebar
I ran this handlebar on my Juiced CCX for a few months and loved it. Basically like a Jones bar with less sweep. I love the aero positions which also seem to allow for better use of my leg muscles. Ran a normal handlebar until just a week ago and just got frustrated on many rides where I encounter high headwinds. I can now ride faster and with less effort (rider and motor). Bike handling in the aero positions takes some getting used to.

27.5x2.6 tires
Although the Surly Troll originally was a 26inch frame, it accommodates 27.5 just fine wth same BB height as most of my other ebikes. I did run 26x2.3 Smartsams for a few hundred miles but felt the ride was too harsh as the surly frame is very stiff. I really noticed the additional harshness due to less tire rollover and will likely never ride 26 tires again. I built a new set of wheels to accommodate 27.5x2.6 Smart Sam tires and they fit the frame just barely(5mm clearance) with the rear axle at the front of the rear horizontal dropouts. I see no reason I couldnt run 27.5x2.8 tires if I slid the rear tire back in the dropouts although all the adapters/spacers would be a nightmare with the GMAC motor. While I like the SmartSams, I also bought some Johnny Watts and ran them for a few rides, settling in on running one in the rear for better tire wear.

Battery
Currently running a 52V 13.5AH Panasonic Battery purchased from Luna in 2018. Powers the bike fine but this pack probably isnt the best/safest for offroad use as it doesnt use cell holders to get all the cells required into the smaller shark case. It also doesnt use individual cell fuses which could prevent a fire if a cell shorts and all the other parallel cells dump current into the shorted cell. Will either go with a Luna Wolf Pack or a pack from EM3EV soon.

Any suggestion/comments on the Luna Wolf Pack orEM3EV batteries would be appreciated
 
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Do you build for others , love the sound of what the GMAC does. Tried to buy a Hilleater with it but they won’t ship to US currently. Your bike sounds awesome.
 
Do you build for others , love the sound of what the GMAC does. Tried to buy a Hilleater with it but they won’t ship to US currently. Your bike sounds awesome.
Nope, dont build for others. Im more of an engineer type than a customer service type. Almost started several technical based businesses but customers are so finicky :D

Have you considered a juiced CCX? I have one and while it was crude (like the hilleater), it was a great bike especially with the HUGE battery.

While the overall power of the GMAC is awesome at up to 1500W, the CCX was very good at 700W-1000W.

I punished my CCX for 4k miles and it held up fine (visually inspected the motor). The CCX did everything I needed 95% of the time, I just wanted to go down the DIY path
 
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I am after a quality bike with the GMAC motor. I loved riding Stromers but had too many quality issues and also would like to pick up the speed a little from 28mph. I am waiting on WattWagons Helios currently which in mid drive . So far prefer rear hubs and of those DD of the bikes I have owned, hoping Helios changes my mind but following the n+1 theory I will need more than just Helios....enjoy your bike , iwill be reading anything you post on it :)
 
I wish I had found this forum before I started my build, but as it turns out I can see how similar other builders' experiences have been to my own. My buiild started with a 10T GMAC hub motor. Initially I had a Specialized Curve frame but had to sell it when I found that the triangle between the upper and lower tubes was not large enough to fit the battery (52V, 20 Ah). I ended up buying a cheap mountain bike in a large size with a big triangle and that worked well.

Some of the modifications I've done to the bike is that I put on a 220 mm rotor on the rear wheel to get more clearance between the brake rotor and the edge of the GMAC motor. I think 200 mm might have worked as well, but with the COVID supply shortage this winter, there were no 200's and only a few 220's. I also put on Magura MT5 brakes as the calipers are slightly narrower than Hope calipers.

Mine is a commuter bike designed to be ridden out to the golf course and back, about a 40 km round trip, but very hilly. I put Blumel Commuter II fenders on to keep me dry and clean(er). On the front fender, I had to notch out the fender to get more clearance on the tire. I found a wonderful product called Mouldable Glue. You simply knead it up into a ball and squish it in place. It hardens into a stiff silicone rubber. It sealed the cutout in the front fender and it doesn't rattle.

I put on the SPL-01 light from Grin Technologies. They are still out of stock but I got one from Hilleater. It's a wonderful light and I really like the 40 LED daytime running light feature. I also added a USB adapter so I could charge my cell phone or Garmin. That is also a Grin product, out of stock, that I got from Golden Motor. I learned the hard way that not all USB adapters are created equal, after I fried my cell phone. I didn't include the cost of the new cell phone into my grand total for the bike, which is currently estimated at around $4K CAD.

I went with the 24 pole PAS sensor rather than the torque sensor, since it looked like it would suit my riding style better. I've been having some difficulty setting it up, as the Grin manual is pretty basic. I've gotten more help from linklemming's posts than from Grin, mostly due to COVID. They don't answer their phones now so all correspondence is by Email, which might mean 2 or 3 days. I've already had one ride where the PAS wasn't set up right and didn't kick in when demanded, but I have a throttle and it sure beats pedalling a 65 lb bike uphill.

Another modification I put on this bike was to add an N-lock stem lock. When you take the key out, the handlebars move independently of the front fork. Not good for someone riding off with your bike, but great for storage, since the bike is only as wide as the pedals. I also added Pinhead locks on the N-lock, Brooks saddle, seatpost and wheels.

Today I'm going to add mirrors to the handlebars and by Saturday it will be warm enough to ride. Really looking forward to that. Hope the PAS is working.
 
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