The Honda CT70 is looking beautiful after its Redline Rebuild treatment and, of course, it’s running like a top. Davin is not one to keep secrets about the work that’s been done and what challenges arose along the way. There were  plenty of updates along the way, but sometimes the best time to talk particulars is when looking at it reflectively. So Davin and lead videographer Ben sat down to talk through the nuts and bolts of this big little project.

First, Davin explains why he chose a Trail 70. “We’d been getting messages about doing something other than an engine for awhile, and motorcycles always rose to the top of the conversation. Between my personal experience with the Trail 70 and its nearly legendary status with enthusiasts, it was the perfect choice.” Of course, when it came time to pick up a restoration candidate, Davin fell back on an old maxim: Purchase the best example you can find to restore. In this case it meant a running and riding bike.

“That machine was pretty tired though. Complete, but tired.” That often makes things a lot easier for a restoration. Documenting how parts fit together during disassembly is a lot easier when they’re all there. Also it can make better financial sense to buy something with parts that can be restored rather than swiping the credit card for each missing piece. Davin guesstimates there are about as many parts into the entire Trail 70 than a single V-8 engine, which means this project might look fairly simple, but it  can also be deceptively complex—mainly to keep organized once it’s all apart.

In that blown apart phase it was all about cleaning and acquiring parts. Luckily, Davin had the experts at Trail Buddy on call to help find and advise on just what he needed. They also helped rebuild the front forks and sprayed the tri-stage candy paint, a paint that surprised Davin both then and now. “It really blows me away that Honda would have done such a complicated paint process on what amounts to a kids bike. These were often used and abused, and that paint makes touch ups really difficult.” No matter when he was re-spraying the entire frame.

Then it came down to assembly, which is where this man thrives. Between Davin’s trusty shop manual and the guys at Trail Buddy, the bike slipped together quite quickly. Now it’s ready for some off road adventures—right after someone puts the first scratch in that beautiful paint. Davin is still a bit squeamish, but he knows that after that first ding, all bets are off. This bike was made to have fun, and that’s what it’s going to do.

To keep track of this and other projects in the Redline Garage, be sure to subscribe to the Hagerty YouTube channel. — Kyle Smith

Thanks to our sponsor RockAuto.com, an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit the Help pages for further assistance.

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Davin and the crew in the Redline Rebuild garage love a giant project, but they love a tiny one, too. Especially since even their small-scale projects are pretty involved. The latest full rebuild to begin is also the first to be finished. That’s right, the 1973 Honda CT70 is done. Might have something to do with the number of parts … Or maybe the fact that Davin used his phone as much as he did the wrenches.

The CT70 is better known at the Trail 70 and served as a literal and figurative jumping-off point for the lifelong passion of many gearheads. Honda introduced the little trail machine in 1969 and produced it until 1981 without changing much. With a lay-down, single-cylinder four-stroke engine, the CT70 is easy to maintain and has enough power to scoot around most adults, although with slightly less vigor that it would a lightweight kid. The easy-to-use, clutchless three-speed gearbox most models featured meant that just about anyone could operate one—and get hooked on the fun of two wheels.

Davin enjoys a motorcycle ride as much as the next guy, but the shop is his happy place. He didn’t hesitate for a second when this bright orange model popped up for sale in the Traverse City, Michigan, area. It was more than a little tired, but the pint-sized bike was complete. “It was really a perfect restoration candidate,” Davin says, sitting atop the finished bike in the Redline Garage. “Everything was there, and it hadn’t been cut up or really abused.”

That made for a quick teardown that left only the bare stamped-steel frame on the workbench. Davin then realized this machine was a little bit outside his normal piston-powered projects. Out came the phone and soon on the other end of the line was Trail Buddy Inc in Zeeland, Michigan. The crew there served as the expert resource for Davin throughout the Trail 70 restoration process. In fact, it was Trail Buddy that helped rebuild the front forks and sprayed the frame with three-stage orange-candy paint.

The 700cc thumper was all Davin, though. “A little engine like this is great for beginners to learn, and really fun for experienced folks, too. There aren’t a lot of parts but they all work just the same as they would in a bigger and more complicated engine,” says Davin. Add in that most, if not all, parts you will need for a rebuild are available and fairly affordable, and you have a great project candidate.

The paint was not the only item for which Davin called in the experts. From the final cam-chain tension adjustment to his dad stopping in to re-cover the seat, this project evolved into a serious group effort. Davin admits the process was more involved than he expected, but he’s still adamant about telling folks to undertake similar projects themselves. “There is nothing wrong with phoning the experts or reaching out in-person to someone who knows more than you do. No one knows everything, and the friends you will make in those conversations can last a lifetime.”

With any luck, this Honda CT70 will last just as long. Where will Davin take this little adventure-ready bike? We don’t even know, but if you want to find out, and discover what is next for the other projects in the Redline Rebuild garage, subscribe to the Hagerty Youtube channel and wait for the weekly updates like the rest of us. We promise it’ll be worth the wait. — Kyle Smith

Thanks to our sponsor RockAuto.com, an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit the Help pages for further assistance.

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As slow as the CT70 will be once it’s done, it is sure coming together fast. Davin is making big strides to tidy up the little machine and ready it for its first outing. Between here and there are some hurdles though, and they have the Redline Rebuild master calling for a little help.

The front end of the bike, which was pre-assembled a few weeks ago, slid right into the steering neck of the stamped steel frame, and a burette that’s normally used to cc combustion chambers in the engine room got repurposed to put just the right 3.5-ounce oil into the fork legs. It’s probably a little bit of overkill on the accuracy, but Davin is not one to ballpark something he can measure perfectly. That might be why he struggled with the second task of the day.

The cam chain has a hydraulic tensioner, but it still needs a base setting. The manual was no help as it says to set the tension with the bike running. Davin doesn’t want to risk damage by starting the engine and then adding tension. That could lead to the chain skipping a tooth and causing valve-to-piston contact. So Davin dialed up Trail Buddy to get get a professional opinion. A quick conversation got the base setting dialed so the engine should be all but ready to start.

Before that first fire up though, the bike needs a seat. It’s been looking awfully naked this entire time, and though upholstery can be an approachable first project, it is Davin’s dad who comes to his rescue this time to make the CT70 seat better than when it rolled out of the factory. A new cover, foam, recondition trim and base all combine to become one very tidy and pretty package when assembled by skilled hands.

Speaking of skilled hands, the engine was assembled by Davin, and that’s why the spark plug fires a strong and bright spark when he turns the kickstarter by hand. Only finishing touches are left, but you won’t get to see this one again until it’s all done and running. We promise it will be worth the wait. Be sure to subscribe to the Hagerty YouTube channel to get notifications with each video that goes up—including the full timelapse of this restoration.

Thanks to our sponsor RockAuto.com, an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit https://www.rockauto.com/?a=HG-YT-21Q3 to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance.

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The orange Trail 70 has been a real fancy workbench decoration for the last six months. All the new and refinished parts have been sparkling from their perfectly organized places in a corner of the Redline Rebuild garage. Now final assembly is underway, and the bike’s current is a unicycle. Davin thinks he could still ride it. We think he shouldn’t try.

Assembling the Trail 70 gives a real lesson in the thrift and cleverness that the Honda designers had back in the late 1960s. There are plenty of 10mm bolts clamping things together, but the gas tank is an example of effective cost cutting. Rather than clamping it in place, there are a few small rubber isolators that effectively wedge the tank inside the stamped-steel frame. A small top plate keeps it all snugly in place. Simple, relatively fail-proof, and easy to assemble.

The rest of the rear end is similar but has a few more fasteners. The swingarm bolts into place followed by the rear wheel, shocks, and brake pedal assembly. For once, things are sliding together easily. Could that continue through the rest of the Trial 70 assembly and first start? Maybe, but you’ll have to tune in to future episodes to find out. Be sure to subscribe to the Hagerty YouTube channel to never miss an update.

Thanks to our sponsor RockAuto.com, an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive.

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We all have when been waiting in suspense for the return of the Redline Rebuild CT70, and Davin is breaking the suspense with a suspens—ion project. The front end of the little Honda is pretty simple, but there is one special tool that—in true Redline Rebuild fashion—Davin elected to build himself rather than wait for the mail.

The first steps are a mock-up of the front-end assembly. A small amount of paint needs to be removed to allow the fork tubes to slide into place in the triple trees, but a small flap wheel makes quick work of that. From there everything slides together and confirms not only that it all goes together as designed, but also that Davin has all the parts ready for final assembly onto the frame. He might have all the parts, but he doesn’t have all the tools.

That’s right, his massive shop full of ratchets and drivers lacks the tool he will need to torque down the triple trees on the Honda. Rather than wait for a tool to arrive in the mail, Davin fires up the Bridgeport to make his own. Some tubular steel chucked in the vice followed by a few careful measurements allows Davin to mill away just enough to create the perfect four-prong tool to engage the top nut of the steering stem. A lug nut welded in place gives him something to put his torque wrench on when it comes time to assemble.

The project is rolling now—well not quite—but at least progress has returned. To never miss an update on this or the other projects in the Redline Garage, be sure to subscribe to the Hagerty YouTube channel.

Thanks to RockAuto.com for sponsoring this week’s video. RockAuto.com is an auto parts retailer founded in 1999 by automotive engineers with two goals: liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit Rock Auto to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance!

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There’s a stage in every project car when a bunch of tasks pile up, and even when they’re completed they don’t provide any obvious progress. It’s one of the hardest phases for any at-home garage mechanic. Luckily, Davin is an expert when it comes to staying motivated and keeping things rolling. The 1937 Ford race car is in that phase right now, but there’s nothing to fear.

The most difficult part of this phase is there’s a lot of work that’s relatively invisible. A couple of examples on the Ford are the roof panel getting straightened out and patched in a couple of places, along with the trunk lid. All this sheetmetal work is a little easier since the race car is going to continue living on the track—not a showroom floor. Davin is rarely a “good enough is good enough” type of guy, but for the ’37 he’s leaning that way about aesthetics. Function over form here.

The trunk lid was hollowed out to save weight and thus is extremely flimsy. There was a brace pop-riveted in place along the back edge, but the look of those rivets was a bit too wrong for Davin. To hide the reinforcement, he instead drilled out the rivets and welded it all together. To keep the weld from falling out the backside of the open hole, he used a small chunk of copper. The weld won’t stick to copper, so it makes for the perfect support in situations like this.

The car may look the same after a week of work, but we promise there are big things on the horizon. Hang in while some of the grubby work gets done, and be sure to subscribe to the Hagerty YouTube channel to never miss an update.

Thanks to our sponsor RockAuto.com,  an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit www.RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have those parts conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance!

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There has been no shortage of heavy metal projects on Redline Rebuild’s 1937 Ford race car, and today is no different. All the fabrication tools and tricks come out as Davin fabricates the steering pieces needed to keep this project on track—literally.

The two most important systems of a car are often the two that get talked about last: brakes and steering. It doesn’t matter how much horsepower you’ve got if you can’t direct and reign in those ponies when the need arises. The brakes are all but sorted out on the ’37, but the steering has a long way to go.

First steps are to figure out the steering wheel location. Since Davin has the seat roughly set, he can decide on where the wheel will sit in the space of the drivers compartment. Then he just has to fabricate the pieces to connect the wheel to the steering box. Sounds easy, right? Well, it kind of is.

The first connection is a ratio box that doubles the input that the drivers puts into the wheel. This means Davin can use the factory-type steering box without having to turn the wheel three turns to get lock-to-lock. Next is to build the shaft that connects the ratio box to the steering box. For that, it’s best to have the engine in place, but the 440 is still torn down and awaiting the Redline Rebuild treatment, so a foam stand-in will have to do.

For things to work properly, Davin decides to move the steering box out just a bit. Of course, it’s never just that simple. Some cutting, grinding, and welding later and the box is held in place exactly where he wants it. Add the appropriate joints to the connecting shaft and the ’37 is one step closer to the track. Progress is progress, even if there is a lot more to go. Of course, in order to see all that work that is yet to be done, be sure to subscribe to the Hagerty YouTube channel to never miss an update.

Thanks to our sponsor RockAuto.com. RockAuto.com is an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit https://www.RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance.

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This week Davin takes himself back to high-school chemistry class as we attempt to tackle zinc electroplating. Requiring only a few materials from the hardware store, this seems like a pretty straightforward process, but projects are never as simple as they first appear. This week’s video is less of a “how-to” and more of a “show and tell us what we can do better.” So, hit up those comments on Youtube and let us know how we can improve our process.

Thanks to our sponsor RockAuto.com. RockAuto.com is an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit https://www.RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance!

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Sometimes things pop up and make you pump the brakes on a project. For Davin, it’s literal brakes that are giving him pause. A lot of pieces on the 1937 Ford race car are unconventional compared to a street car, but that hasn’t tripped him up to this point. Now the shoe is on the other … backing plate?

The brakes of a car designed for only taking left turns are designed and implemented radically differently than anything you’d find on a mass-produced car. Typically, for a race car like this, brakes are set up in a such a way that applying them will cause the car to pull left and thus can be used to help get around the track faster. One could use hydraulic valves and limiters to achieve this, or in the case of the ’37 here, the previous mechanic removed friction material from the shoes to proportion the braking force.

Davin knows he will want to tune the brakes, but for now the primary focus is to make them functional. That is why the first task was disassembly and cleaning. Of course, be sure to snap a photo of the assembly before taking things apart. Even if you don’t need it during assembly, it could be handy in the future. Digital photography is basically free these days, so snap all the photos you can.

Assembly was when the problem appeared. With everything back together, there were some small fitment issues that just bugged at Davin. The 12 x 2-inch brake shoes are odd-sized and none of the options he could get his hands on fit to his liking. So, he sent the original shoes out to be re-lined. Fresh friction material made those old pieces as good as new and they fit perfectly. The assembled backing plates were then put on the shelf with the finished drums and hubs.

The brakes might be coming together a bit more slowly than ideal, but that is not going halt progress on this race car—or any of the other projects Davin and the team have running in the Redline Garage. If you never want to miss an oil-soaked minute, be sure to subscribe to the Hagerty YouTube channel and watch for new episodes every week.

Thanks to our sponsor RockAuto.com. RockAuto.com is an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit https://www.RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit our Help pages for further assistance!

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The small scale of the Honda Trail 70 means updates and progress happen fast. For example, Davin took a trip to the machine shop to get the precision bits cut to size and ready for assembly. Then he couldn’t help but go ahead and put it all together too.

The cylinder was the first thing to get mounted into the machines at Thirlby Automotive. A quick pass with one of the smallest boring bars in the shop brought the bore not only to properly round, but also to the size appropriate for the new piston. Final size was set with the hone to make everything just perfect. From there the attention shifted to the cylinder head.

The valve seats and corresponding valves were not in the worst shape, so the team decided to cut the valves and give a quick grind to the seats. This created fresh sealing surfaces to make sure the small valves won’t leak. It’s a simple process that requires a careful hand when dealing with parts this minute. The team at Thirlby provided that steady hand, and the finished product was soon ready to head back to the Redline Garage for final assembly.

That assembly went fast, but it was important not to miss any of the precision checks in the flurry of assembly excitement. Take the piston ring end gap, for example. The shop manual laid out the specs, and Davin got lucky that the new rings were perfectly in the middle of the range that was called for. Some oil and the cylinder slid down over the piston, followed by the cylinder head and valvetrain.

A couple of final touches and the engine was complete. It’s now ready to be slipped back into the chassis. If you want to see that, you’ll have to tune into a future Redline Update. Make sure you never miss an update by subscribing to the Hagerty YouTube channel.

Thanks to our sponsor RockAuto.com. RockAuto.com is an auto parts retailer founded in 1999 by automotive engineers with two goals: Liberate information hidden behind the auto parts store counter (by listing all available parts, not just what one store stocks or one counter-person knows), and make auto parts affordable so vehicles of all ages can be kept reliable and fun to drive. Visit RockAuto.com to order auto parts online 24 hours a day, 7 days a week, and have them conveniently delivered to your door. Need help finding parts or placing an order? Visit Rock Auto’s Help pages for further assistance.

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