Recycled Cycle

[kirrbby]

Had a little time at work today, and I made myself a wedged spacer to use with my original carb/intake. It looks really good so far. I'm thinking I'll just glue it right to the stock atc125 heat spacer. But with the custom wedge, my carb sits pretty nice and level...with the intake sitting on a flat surface. Hopefully it'll be the same on the bike.

Some pics.

 

[69ST]

Nice workmanship, Mr. B.

Not knowing the structural properties of the material you used, this is one of those rare instances where I'd suggest using an adhesive/sealer between the spacer & intake. Gluing it on the one side should add frictional support and help keep it from splitting at the thin side. Just a thought...

 

[kirrbby]

I'm sure the milage is pretty close. I DO fill the tank to within a bubble ofthe filler neck. Then I warm it up for 10-15 minutes. Then, both rides I took one short break, and both hit the reserve right at 30 miles.

Another beautiful day. I had a hour before dinner, but I decided to take my Cruiser out instead.
Once I get my Black and Red tagged, I'm gonna take it for a half a day jaunt...long awaited jaunt on this bike.

My #1...the 125 Dax, hasn't been seeing much action lately. This Black and Red bike will be competing for the #1 spot I think. It's a ton of fun...similar to the Dax on the street.

I started with 1/4" micarta. It needed to be about 3/8". It IS really good stuff tho. It's resin with multiple layers af some kind of fiberglas (or other) mesh. It should hold up really well, for sure if I glue it right to the intake. Then I can tweak the port match on everything. I think it will work out really well. I'll glue it all up with Seals All, I trust that stuff long term.

 

[fatcaaat]

i don't know guys...i've been using the atc125m intake/vm20 carb combo for over 15 years and never had an issue with float or the fact that it isn't perfectly level. Never. As a matter of fact, the video of the orange bike i just posted with the trx90 kickstart conversion has this exact combo and it idles all day long and runs out cleanly.

Ever since i've had actual ice form on my intakes when decending long mountain runs, i have elected not to use a spacer between the head and intake manifold unless i had a clearance issue. However, when given a choice between the fiberboard, nylon, or aluminum spacers, i'll use the aluminum.

And if it helps with jetting, i am jetted 20/140 with this engine, trx90 bottom, 52mm popup piston, stock trx90 head ported with z40 cam, atc125m intake, vm20 carb, and chinese 125 ct70 replica exhaust.

 

[kirrbby]

I've been hoping to hear from you about my troubles here Fatcaaat. I know you've ran this setup a lot. I'm not convinced that the real trouble wasn't just ME.

It's taken me a good lot of head scratching and sweat to arrive at this point. I expect to install this VM20/atc125 intake setup. Jet it, quick and easy. And be done monkeying with it. My wedge spacer will level out the carb, which has to be good. I shouldn't need a spacer between the intake and head...I hope. If I do, I'll make one from aluminum.

 

[69ST]

I agree with Jarred on this one, aluminum is the best material for a spacer...given my druthers. That said, I've been running the same 22mm intake/VM22 on my stock Nice...with the supplied phenolic spacer at the wrong (carb) end for 14 years & ~23K miles and the only time it's a problem is when ambient air temps dip below 70F. Even then, the hiccups are relatively minor down to ~60F. Below that temp, the bike is parked.

The great unknown with your setup, is how much vacuum it generates. I expect that it will be higher, at speed. The stronger the vacuum, the greater the refrigeration effect (a.k.a. latent heat of vaporization) and the colder the intake can become. I've seen some intakes bolted directly to the head, no insulator at either end, that got cold enough to sweat like a glass of iced tea in 95F ambient air. No need, or point, in over thinking this. Run the bike and see how it goes. You'll get a definitive answer soon enough.

 

[Gary]

Bringing back memories kirrbby. Had to go and dig thru my pile O'parts. Back in 71 I don't think many "performance" parts were available and if they were I didn't have money for them. If I did have money I'd just get a bigger bike anyway! A friend gave me a S65 motor with the intent of putting in the Z50. Existing manifold was quite different shape so I figured out to make a spacer much the same as yours except we did not have the experience,tools or materials you have today So we made it out of wood :9: and coated the inside with some sort of epoxy so the fuel would not soak in. Honda had the same problem with carb icing so they plugged the oil feed at the case to cylinder junction ran an oil feed line from a boss on the side case thru the carb and then back to a boss drilled into the cylinder so the oil could continue up to the head.In these pic's you can see the oil feed connection and chamber cover on the carb which by the way is a 19mm unit. You can use a S50 (very rare) or S65 clutch cover on a Z or CT cases by just plugging the oil outlet.





Here is the plugged oil outlet on the clutch cover-



Here is the return from the carb to feed the upper end-



Now you know why every early cylinder has that boss cast into it,the S50/65's were the first of the long line of the OHC engines we know today and were first offered here in 1965



Keep in mind the year but my Z with this engine,which was rated 6.22ps @10,000 was pretty quick. In this time frame most other kids had lawn mower engined bikes,here I show up with my bike which still to the untrained kid eye has not changed. Unfortunately I have no pictures of it being on.

Sorry for the lecture,class dismissed

 

[69ST]

...
Keep in mind the year but my Z with this engine,which was rated 6.22ps @10,000 was pretty quick. In this time frame most other kids had lawn mower engined bikes,here I show up with my bike which still to the untrained kid eye has not changed. Unfortunately I have no pictures of it being on.

Note, 1ps = 0.9859hp

6.14hp from 65cc is pretty healthy. A stock CT70 makes somewhere between 4.5-5.0hp, depending upon the source.

 

[Coastal Redneck]

Dammit, Gary, life is too short to be sorry, and whaddya mean by "class?" Ain't no class to be found here, LOL... oh, wait, there's always OLD CT, LOL. :41:

I think these stubbies are FINALLY taking effect, WOOHOO!!! Shoulda gone with the Bloody Marys or homemade Pina Coladas in the vintage blender... meh, Pool Shark Doug & his gal are probably coming over tomorrow, we'll do the Pina Coladas then, aye? :4:

I'm back to entertainment on the 65" curved screen, that "RAMBO" ('08 version) flick was HILARIOUS on the big screen, the exploding Burmese army fooliots made my day, LOL. Of course, I'm a sick bastard... and LOVIN' IT, 10??? :30:

 

[Deoodles]

Kirrbby, That spacer looks good. If you have issues with icing you can always trim the manifold with a harbor freight chop saw to get the angle without a spacer. I did that on my 108 to lower the carb so the stock airbox fit. It works well and has been trouble free for a year now.

 

[kirrbby]

That's a good idea Deoodles. I glued my spacer in, between the manifold, and the stock spacer. Just need to clean it up a bit and ream the mounting holes now. Then I'll make sure the ports match up nice before I repaint everything. I don't think I'll have any icing issues at all. I'm not using a heat spacer at the head. The manifold has always been quite warm on this motor.

 

[kirrbby]

Bringing back memories kirrbby. Had to go and dig thru my pile O'parts. Back in 71 I don't think many "performance" parts were available and if they were I didn't have money for them. If I did have money I'd just get a bigger bike anyway! A friend gave me a S65 motor with the intent of putting in the Z50. Existing manifold was quite different shape so I figured out to make a spacer much the same as yours except we did not have the experience,tools or materials you have today So we made it out of wood :9: and coated the inside with some sort of epoxy so the fuel would not soak in. Honda had the same problem with carb icing so they plugged the oil feed at the case to cylinder junction ran an oil feed line from a boss on the side case thru the carb and then back to a boss drilled into the cylinder so the oil could continue up to the head.In these pic's you can see the oil feed connection and chamber cover on the carb which by the way is a 19mm unit. You can use a S50 (very rare) or S65 clutch cover on a Z or CT cases by just plugging the oil outlet.

View attachment 34840

View attachment 34841

Here is the plugged oil outlet on the clutch cover-

View attachment 34842

Here is the return from the carb to feed the upper end-

View attachment 34843

Now you know why every early cylinder has that boss cast into it,the S50/65's were the first of the long line of the OHC engines we know today and were first offered here in 1965

View attachment 34844

Keep in mind the year but my Z with this engine,which was rated 6.22ps @10,000 was pretty quick. In this time frame most other kids had lawn mower engined bikes,here I show up with my bike which still to the untrained kid eye has not changed. Unfortunately I have no pictures of it being on.

Sorry for the lecture,class dismissed

Good stuff Gary. Pretty impressive work for a youngster.

 

[kirrbby]

Took my Black and Red to the car wash today to rinse off the dirt. Took a quick blast after, to get the water out of the nooks and crannies. About a half mile from home, after a high speed stretch, it started knockin. Not ticking, but a big loud knock. I was pretty worried. Long story short, my cam gear bolts we're about 50% backed out when I got it home...rode it home. Not too sure what was making the actual knocking sound tho. Anyway, one of the bolts was stripped, other was...ok, but not the best threads on it either. The cam chain had been rubbing on the small locating boss on the cam gear cover. That was the only other damage that I seen. Replaced the bolts with 2 good used, with blue loctite, and the knock is gone. Changed the oil for good measure...I think I might be ok now. Maybe lucky it happened close to home.

I don't know if the screws were bad when I installed them. Or if I didn't torque them properly, and they were damaged when they loosened up. No matter, loctite on all cam gear bolts from this day forward. And, I'll check them again after the next few rides.

 

[69ST]

If the knocking was cam bolts against the aluminum cover, you've probably got a ton of stardust in the oil. (It could have been the cam sprocket slapping around.) The good news is that aluminum, being softer than steel, probably won't hurt anything. If it were mine, I'd check the oil spinner contents and plan on a couple/three quick oil changes to flush-out any metallic bits...unless you didn't find any (that'd be a really lucky break). I've seen this happen more than once and the engines survived.

I'd say that you were very lucky to be close to home. The impulse is always to limp a machine home...which could have done some real damage, with just a little more runtime.

BTW...I always give oiled threads a good shot of Brakleen before applying Loctite.

 

[cjpayne]

That was CLOSE there kirrbby. Do you think the cam threads are damaged too. I would want to change the cam, unless those new bolts tightened up pretty good.
I agree with Bob about the stardust and would do a good flushing and spinner check. Maybe pouring oil down into the chain area with the cam cover off will help? After that, lean the bike over and pour oil down with the stator cover off?

 

[kirrbby]

I'm due to clean the spinner anyway, so I can definitely do that. I didn't see much missing aluminum tho...maybe the equivalent of a steering stem bearing. And there wasn't much stardust or aluminum shrapnel in the oil either.
I did think about brakekleen for cleaning the threads for loctite, but not till after I had it back together...typical. I'll redo the loctite too...maybe when I recheck those bolts.
I mounted my cheap Chinese tachometer on this bike today so I can see how high it's revving at high speeds...with the 16/33 gearing. Then I'll check it with 17/33. I'd like to put a number on the revs when they reach..."cringe level" to my ear/brain. Wondering if I need to let it scream, and maybe add a billet clutch. Or, tone it down enough so I don't need to upgrade the clutch.

Question...can I put all of my stock Honda manual clutch innards into the tbparts billet clutch basket? Or do I need to buy their basket plus THEIR innards?

 

[kirrbby]

PS... I recommend this bike to everyone. Buy it or build it or whatever you gotta do to get one.
CT70 HK1 with a tb 117cc with race head, and a super stealth exhaust.

It's quick and light and a super fun ride, anywhere you take it. VERY highly recommend :--)
>>>Or a V2 head...might be even better.

 

[69ST]

I like your idea of slapping a tach on the motor and finding out what it's spinning. This could be much ado about nothing. AFAIK, 10K should take you to 70mph and that's pretty impressive speed from 117cc. If you're never twisting it higher than 10K, your existing clutch will be fine.

I've never been 100% clear on the TB/Honda clutch parts interchange. May as well start with the billet basket, since that's an upgrade for the basic TB clutch. Worst that could happen is you have to place two parts orders instead of one.

As for cringe-level rpm...I'm with you on that one. Jarred and I have been bantering this topic back & forth for years. In my carefully-considered opinion, any stock 49-110cc motor (I'm only referring to Honda lumps, here) can spin at least 8000rpm until the tank is empty. That includes the long-stroke (55.5mm) Nice. Pretty much any of them can survive 10K...though few make power at that speed. We've heard from owners of 12v (1991-94) CT70s cruising along near 50mph, for miles at a time...and that requires north of 10K.

Even with a 51mm crank, your 117 has a rod/stroke ratio that'd make a lot of racecar engine builders envious. The reciprocating assembly won't reach critical speed until it's spinning in the mid-teens(!). From what I recall, it reaches peak power around 11K and can be twisted tighter than that before the power curve goes off the proverbial cliff. Circa the late `90s, I started hearing about the stock clutch basket coming unglued around 12k, and 11K became the maximum recommended speed for a primary (crank-mounted) clutch. For that reason, I'd want the billet basket on any engine that'll see 11K, or higher. Never know when you might miss a shift.

FYI, the other workaround (one that I prefer, given my druthers and the budget) is a secondary-mounted clutch...like the Nice and copies of that design, have. Converting a primary setup to a secondary costs more than a complete TB117. Needless to say, it's not a popular project.

 

[kirrbby]

I know that a milk crate is the period correct part to strap down onto the luggage rack when you want to haul your poodle, or get the groceries. But...I decided I had to build one that would fit a little better. Still looks kinda big on there I think. This will allow me to leave my backpack at home when I ride to work. And I think a 12 pack would fit in there.

Whadda you guys think?
Be honest...it's ok.

 

[kirrbby]