Engine assembly is DONE! Honda CT70 project continues | Redline Update #90

"The Honda CT70 restoration continues as Davin gets the complete engine back together. We start with a trip to see our friends at Thirlby Machine Shop to bore the jug and do some valve work on the head. Once back at the shop, Davin gets to work on the final assembly, including setting the point gap and making sure the timing is set.
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[@sadubone]

I love the fact you make no qualms about showing you reading the manuals for specs. The attention to detail is what sets your engine building apart from others I've watched. Thank you for sharing. Such an awesome little engine.

[@belyear]

I thought the same thing. Makes sure that it’s right.

[@keithchilds3105]

What was the site you got the manual from would like to grab one

[@sadubone]

@@keithchilds3105 send the question to Hagerty not me. I have no idea.

[@EllisFamilyBusiness21]

I am the grandson & son of original owners of Sandusky Motor Parts & the original dealer & seller of that Honda CT 70. We couldn’t be happier to see that bike still bringing joy happiness so may years later. We are also happy to see you restored our dealership sticker to pass down with the history of this bike for many more years to come. From the Ellis Family THANK YOU Raymond Ellis lll Ellis Family Motorcycle & ATV Repair Im sure Dad & Grandpa are looking down proudly 🙏 🙏

[@garthhowe297]

You don't see a 70cc get that much love very often. Can't wait to see it run.

[@hitnorcal]

The machine shop portion is exciting for me. I love to see it.

[@Timmayytoo]

I know - I'm sitting here watching that and thinking I should have gone into that out of mechanics school instead of general repair (which I could only stomach for 4 yrs)

[@Dave-from-Mercer-Island-WA-USA]

This family of engines have been a part of my life since I was 14. Outstanding choice for a project.

[@randy1ization]

been part of mine since I was 7.. got my first concussion on a z50

[@bigears4426]

With these a oring goes on the head gaskets and a copper washer on one head stead as the oil goes along side the stud. Honda the best little engines by far

[@RestorationObsession]

Don't discount yourself, Davin. You deserve most of the credit! You're a total badass. So loving this rebuild!!!

[@GeannXD]

Hi Davin, I love your videos, I'm a marine diesel mechanic, learnt lots watching you. PS: my wife hates when you say "get out in the shop, get your work done". She thinks is rude. Hahahaha

[@cheesemons]

The calm music just suits the calm engine building. Love it when everything goes perfectly to plan.

[@chemxfan]

The polishing & chroming of the aluminum is a nice touch, & it will complement the body & paint work on the frame. Overall, this is a nice build.

[@rainsilent]

Honest confession: I don't like motorcycles. They just don't appeal to me. That said I do have a massive appreciation for the mechanical artistry and craftsmanship that goes into them as it is fundamentally no different than what goes into cars or aircraft. That is what made this video so enjoyable for me to watch. Watching the working skill go into the engine is a wonderful thing. Great work and thank you for sharing.

[@adamdelarozza1985]

Your shop and assembly station is super clean and down eight excellent! I strive for a shop as nicely kept as that one shown, very nice work.

[@heidhouarbi]

Best performance. Best tool. But the most important the best mechanic skill worker

[@jeffplant3]

I think this is one of the coolest projects you've done. The fact that it's miniature allows us to see all the mechanics in a very focused manner. It's great. Also great teamwork. Can't wait to see it finished. Who is going to be riding it!!??

[@DetroitMicroSound]

Great project! I'm about to buy an orange 1972 CT90. 😁

[@blairguinea6811]

an engine rebuild is an engine rebuild no matter what size, thank you Sir

[@Onewheelordeal]

Rebuilding a 1967 CM91 currently, those guys at Honda sure know how to whip up a motor The way that case just gleams has me drooling

[@moparedtn]

I've always loved watching people who are damn good at what they do - hence, why Davin is a favorite here on Hagerty, along with Tom (just where the hell IS Tom, anyways?) -Ed on the Ridge

[@ckane510]

I don't know how many of those motors I worked on in the 70's. All I can say is LOTS!

[@gunny2shoes102]

brings out the kid in us, glued to this build.

[@BWGPEI]

A minor tower of power coming right up. Glad to see you having fun and hope you actually get to ride it.

[@PenkillerDIY]

You are a treasure of a man, spreading the wealth of knowledge.

[@adlihafidzuddin3968]

in my country,we does these engine quite often. 70cc,125,135,150 4stroke and 2stroke

[@bengy1977]

Great work as always. And it is good to see you referring to manuals as well. Hard to keep it all in your head right.

[@Paulster2]

"That'd make a great coffee cup, just seal up the bottom of it ..." ... it's good to see Davin has priorities :o)

[@chrisrhodes5464]

I love watching this build

[@duckysan]

So impressed with your production values, photography and easy to understand descriptions. Well done, and keep it up!

[@andrefarden9220]

Excellent video. It was great to see it come back together. The chromed tappets and cam cover really add a nice contrast. I can’t wait for the complete bike.

[@f1hotrod527]

It is fun to make fun of this engine because it is so small. But this engine deserves the respect of being one of the great internal combustion engines of all time. I believe this engine or versions of this engine were used in many of Hondas small bikes, and there were probably many millions of these engines made, and all of them did their job to perfection. Truly beautiful design.

[@robertlambert5299]

I’m liking the 70 episodes. Nice work guys.

[@erichildreth7562]

Man it is coming together!! Can't wait to see this all back together and we know it will look and run great because of the fantastic work that you all have put into it! Thanks for sharing!!

[@Damien.D]

There are some serious wizards in this machine shop. I always love to see this magic being done. Also if you find these valves and camshaft tiny, try to work on a Honda GX25. It's a complete 4 stroke OHC engine for string trimmer. 25cc. Or one and half cubic inch. Valves are less than half an inch in diameter....

[@2ndspingarage]

He looks so excited working on this, dude you're facial expressions on everything Crack me up!

[@psirider]

At 4:50. I enjoyed seeing a pro do that. Always heard not to. But I do it anyways no ones got time for wrist cramps.

[@seanstone70]

Loved this one I remember those little bikes as a teenager 👍

[@emceestacksone4805]

Been working on Honda CT horizontal replica engines love this content 💯

[@DracoOmnia]

One helluva thick walled coffee mug, lol. Awesome stuff, this little project is too cool.

[@jp2246]

Gear heads hot rod everything!

[@ronlynch7744]

The motor & Trans are looking super clean. 😎👍🇨🇦

[@jftjft5962]

Thanks for sharing so much detail in the video. Great series on the Honda 70 build.

[@broo_shs]

back in day my step-dad Friend who was a machinist,Teach Me Do Metal / engine Work,But my first moped Was Honda monkey 90cc Dax in 1983 frame, i was about 10 years old so we made a lot of work and we did all ten yards what in that time can be done, but its was fun Project.

[@levisylvester]

12:43 lost the right nut? Great engine build! Better than new!

[@jamesdiehl8690]

Man, you guys are strong lifting that jug like that! 😀

[@truthseeker5968]

I love these old school places.

[@patbullard9276]

First time I’ve seen an engine stand that I could describe as, “cute “.

[@sonyhk3824]

Great job Davin 👍. Cheers guys

[@budisandjaya7956]

Amazing Good luck, waiting Test drive 👍👍👍

[@kyleforeman4543]

The hole process just shows how many people for each of their expertise touches a big or small engine,,another great video,,great reading the good old manuals, an white towels,lol lol .carry on..😎😎✌✌🤙🤙👍👍

[@mmazz30]

I wonder how many people have been caught out forgetting to put the o ring seal in the head gasket between the head and barrel?

[@broo_shs]

you can drill pore couple of mm to the bolts hole, and put 3mm sleeve on that to get bigger piston, that we did one of my honda dax.

[@TkngSantet]

in Indonesia,we call it C series..... extremely modified with stock head an block valve 28 in en 24 on ex in piston max if using stock borring(block) max 54mm also some modified in stroke as like stroker kit if in my place we change oil pump positioning

[@jimmymorrison3973]

What a beautiful little engine!

[@MrGreen7427]

Love seeing this perspective on building a ct70. 😊

[@Cartier_specialist]

Owners of 2 stroke dirt bikes get really good at changing out rings. I can tell you because I am a previous owner of one.

[@scrappy7571]

Cool how they used the connecting rod hone for the cylinder bore. Guess they did not have a hone for coffee mug size bore!

[@jamesdiehl8690]

You can use springs out of a ballpoint pen, and a paperclip for retainers or a twist tie. 😜

[@charlesharper7292]

Great little engines.❤️

[@LIVE3DPrinting]

Great video Davin as always. I am going to give a bit of insight here though, I know that #1, your videos are NOT tutorials and #2, motorcycles are not your specialty. That being said, if anyone uses this for guidance please do NOT regrind the valves or seats! Buy new valves (they are available). From the factory the valves have a hardened face as well as the seats. Grinding removes that hardened surface and drastically shortens their lifespan. I have fully restored a couple of these as well as the 50cc (Monkey) version for customers. Fun little bikes and super reliable.

[@alotl1kevegas860]

I don't think the monkey had titanium valves. Pretty sure they're stainless, which is 100% okay to re grind

[@LIVE3DPrinting]

@@alotl1kevegas860 They aren't titanium or stainless, they are hardened steel valves.

[@99unclebob]

exactly my neighbours growing up in the early 70's when these first came out in Canada and the US had half a dozen of these and we road them hard almost daily living a quarter mile walk to the monkey trails and we over heated more than one of them and our dads made us rebuild them ourselves with their supervision and we always got new parts especially valve assemblies and seats for this reason and both our dads were machinists,[ we were lucky that way] we had to pay for the parts from our paper routes and it took couple of weeks to do it and pooled our money together as kids for parts and gasoline, new parts were cheap back then and a dollar was still worth dollar, great video Davin and the chromed parts look really cool. 👍

[@alotl1kevegas860]

@@LIVE3DPrinting ahh, in that case definitely replace them. Im not familiar with these Honda monkeys. Im 31, they were before my time lol

[@LIVE3DPrinting]

@@alotl1kevegas860 Sad to say, but they weren't before mine! Dangit!

[@williamvanderjagt-5p1nad30]

Did the machinist ust the rod rezizing machine to hone that cylinder? Genius!

[@RicardoRodriguez-mh7my]

man this guy has some tough but kind eyes

[@oldtown6240]

Excellent - it is something I always enjoy.

[@juanlopez1635]

Thank you!!!

[@giancarlopbranco]

What a nice job! Congratulation!! 👏🏻👏🏻👏🏻👏🏻👏🏻

[@syarif_rc_channel]

If you are interested, try building a Honda cub125cc engine with the KPH type, this type is better because it has an oil squirter behind the piston and also a more reliable oil pump gear. and also has a roller rocker arm, and also a 6 spring clutch housing, and is also ready to stroke up easily

[@johna1160]

All those fins will keep your coffee nice and cool. Wait a minute...

[@autka_me]

4:47 I was bit stunned to see valve lapping with drill. Maybe something changed, but to me it was always a manual job that required constant changing of valve orientation and grinding direction so that grains in lapping compound don't make grooves that go all the way around valve - seat contact surface thus lowering sealing. Is this still a thing, or there is now some new technology compound or something?

[@marcryvon]

The well experienced man surely changed the orientation without showing it. A small change in angle is sufficient.

[@elobiretv]

I don't think anything has changed, people just use a drill to save time. Anyone who thinks it's a good idea needs to do some research

[@joejoejoejoejoejoe4391]

I wonder how many of those engines are rebuilt on a special stand, in such clean conditions like that, or on a mucky bench/concrete floor with some eager teenager bashing it with a hammer.

[@michaelmanning97]

Always great stuff from you all.thanks👍

[@achmadsuwito2017]

Usually, in Indonesia, super cap motorcycles just replace the piston noken and the carburetor. keep on porting

[@aditya9942]

Noken = camshaft

[@7d_cholidramadhani165]

luar biasa, sangat rapi dan bersih pengerjaan nya

[@electromech8931]

they are pro professional ....! very good job..!

[@Guardducks]

Rock on Davyn. 🤘

[@callmechanic521]

in Indonesia the type of sleeping machine 100cc+ is very familiar, and he is very smart to increase his clinder to two or three, especially when it comes to borep up engines👌😁🇮🇩

[@Tomo125]

Senengnya pitung direstorasi, ditempat kyk gtu 🤣

[@brollin2flybrollin2fly49]

Great job thanks

[@mulyadi_RGS]

We got huge community for CT70 bike. Peace fr Jakarta

[@buijantjung8401]

Awesome 👍👍👍

[@ALABAMAHEADHUNTER]

Always enjoy your videos !

[@agussubekti9427]

Easy to practice

[@meyhaqim9090]

It clean.i love.

[@jeremymurphy7320]

5:20 Bah gawd that thing's got a hemi!

[@jerryray5840]

That's sweet!!

[@yves2075]

Mod an engine, upset its balance, dramatically shortening its lifespan. Squeezing a handful of HPs. Apart from that, beautiful work, and plenty of fun! Keep machining, guys.

[@5tr41ghtGuy]

That CT-70 engine is seriously detuned. I had one of those bikes, and and friend of mine had a CL-70. The CL ran *way* stronger than the CT!

[@ALABAMAHEADHUNTER]

You guys really need to do a Subaru . I have rebuilt a few of them .Only engine I have done that the block has holes in it so you can install the wrist pin and snap rings .

[@garlandhenry6792]

Great job really enjoyed it

[@mohdhalimamat1147]

Still on the contact point system or changed to electronic cdi system?

[@sahabatbonsai8864]

Mantap, pengerjaan dengan alat alat canggih

[@lakmoondaulay]

Perfect, nice, well done. 👍

[@manuelmartin5844]

This baby piston y lovely

[@masheralive3025]

this engine is every pindi boii wet dream

[@malikhammad1416]

That engine very common in Pakistan and recently i built it by my self. And y its popular bcoz its a fuel efficient and powerful even it carries 3 person easily onto it and also Honda is also giving this old model in cd 70

[@baazigaj9125]

great video... you look sickly bro.. take care

[@jagvette1]

Now the Honda engine has so much extra power you can put it in the racing car :)

[@milt6208]

When in doubt get a pro to help. You are allowed Davin.

[@Galaxy-jk5ko]

Malaysia very upgreat..big piston..

[@maldo72]

love these videos

[@clryll]

Man I Love if Hagerty would restore my HONDA XL125S would be great

[@genka2237]

Хорошая работа 👍

[@curvs4me]

You gotta Set the ignition advance to spec within the point gap range. That's a HUGE amount of difference in ignition timing with a 3 thou spread. Use a meter and check for continuity at whatever timing should be. This is where all the power is won or lost in vintage outboard and motorcycle racing. You don't have a distributor to turn, so timing is set rough with the stator plate and fine tuned with the Point Break. Older scooter and moped guys, this applies to you as well.

[@curvs4me]

I'll add a caveat, it's not really on you if you weren't involved in engine building and tuning of small racing engines. It will run anywhere in the specs. However you can be giving away as much as 40% of your power. Anyone that went to go kart tracks in the 70s and 80s, the point gap was the difference between the one really fast kart and the one ridiculously slow kart. Even holding the governor wide open wouldn't make the slow one go LoL.

[@ronb7105]

Used to static time these with a cigarette paper, just so you can pull it out at the fire mark.

[@frankzane7326]

50hp?