Touring on a ct70. What engine to use?

[racerx]

Originally Posted by ghunt

Where can I get a nice motor that needs to be rebuilt. And how does the 110 compare with a bored and stroked ct or sl motor like 117. As far as power and top speed.

That one's a bit of a loaded question. A complete TB117 kit, fully optimized, should be faster than a stock Nice 110. The Nice is good for low 60s, the 117 should be good for 70+. That's because, in addition to more displacement, it's basically a race setup- designed to make top end power. It should be a rev-happy motor compared to the Nice. It's more screamer, the Nice is a stomper... tuned race motor compared to bone stocker.

It's in areas other than outright power where the Nice shines (and I'm not knocking the TB 117). The Nice makes good useable power at speeds below 60mph, it's a long-stroke torque monster and can be built into a reliable big-displacement powerhouse, just not on the cheap. 122cc is pretty easy, 127 a lot more but that would give you 70-75mph, maybe a bit more depending upon the rest of the mods. These motors, in decent condition, don't break and they are silky smooth. That describes the clutch and gearbox, as well, which began as 110cc parts. The CT70 motor is a 49cc lower end. The electrics of the Nice are not only 12vCDI, but roughly twice the output, allowing a 35w/35w headlight that actually produces light.

Cost wise, it will depend on whether you upgrade your 6v electrics, clutch and transmission. I reckon, that no matter how you slice it, it'll be fewer dollars per hp. However in terms of cost per mile, the Nice will come out ahead. That's about it for quantitative comparisons, the rest is qualitative (read: "subjective") one of those apples-to-oranges comparisons. Different people prefer each, both have their good points.

[HymieP]

Honda Nice will be the least expensive, if money is no object go Takegawa or the big Honda Nice. From what Racerx tells me though, tuning can and will come into play on these big boys. Good luck.

My avatar is a pic of my brand new Honda Nice and it's a beauty if I do say so myself. Well worth the money IMO.

[chuckklr04]

Update!

140 lifan installed and running. Need to clean up the wiring and install clutch cable,lever, footpegs etc.

As I might be laid off in 09' the trip may take a different spin and be a little longer. May even pass her along to the next laid off biker.

Laid off trail 70 panhandle tour - ADVrider

How many miles can a CT70 tire go?

[racerx]

Extended 50-55mph cruising stressess the engine very differently than trail riding. Mainly, it's going to run a lot hotter. Lifan sets up the piston & cylinder "tight & rough", so break-in becomes more of an issue. I've seen guys beat on these motors with next to no miles on the clock and then wonder why the top ring land broke. Keep the revs & temp down for the first few hundred miles, change oil frequently until both temp and the quantity of metallic "stardust" in the old oil both drop-off. Clean the oil spinner after the first 300 miles. You may need an external oil cooler to keep oil temp below 230F (ideally 190-220F). You'll also want to get the carb jetting and gearing optimized. Lean equals hot, not good. As for gearing, assuming 70mph top speed, I'd shoot for 55mph in 3rd; that'll give you a good climbing gear for extended grades and 4th will be more like an overdrive. If you can knock 500rpm off at 55mph, it'll make a surprising cumulative difference over several thousand miles. I'd try to get 1K on the motor before hitting the road for real. That ought to be enough to get everything tweaked, stable and become familiar with the little peculiarities of this specific bike.

For an OEM Bridgestone Trailwing, 4000 miles on pavement is about it for the rear. The front will last a lot longer. The Kendas mentioned elswhere may last longer. As I recall, they use a harder rubber; the tradeoff is less traction on pavement, especially in the wet. Tire life isn't the only thing you should consider; chain life is just as important. Consider spending a $40 bill on top quality Iris or DID NZ series chain. I've gotten as much as 5500 miles from these, never saw more than 1000 miles on the cheaper stuff. A worn out chain will ruin the sprockets.

Lastly, I'd recommend carrying less than 3-1/2 gallons of gas. It's not all that practical and are you ever going to venture more than 300 miles between gas stations? Drop down to 1 or 2 gallons and you'll still get 140-250 mile range. Use the space savings for a spare drive chain & master links, plus a vinyl-coated motorcycle cable & tubular-key lock. A little bike is way too easy to steal.

Okay, that's by no means a "be-all/end-all" list, but it should get you headed in the right direction for a mechanically uneventful trip.

[bjatwood]

chuckklr04 I will be following this build and the trip. Sounds like a fun/ventfull trip. It will be interesting to see how that engine holds out and what kind of issues pop up. Please keep us posted on your progress and keep a journal of the trip. If possible.

Brian

[TrailRyd3r]

Grats on the 140. It is a great motor, it wont let you down.

[chuckklr04]

Would like suggestions on gearing. Buying sprockets and tires today.

Gonna go with the Kendas tire wise. Replacing the bearings in the hub at the same time.

CS? 2 teeth more than stock?

[racerx]

If I correctly recall your comments from the linked thread, you're planning quite the extended tour & without support. Hence the suggestion to thoroughly shake-out the motor and carry a few spare parts.

You're going to have to do some experimenting with the gearing. Working things out mathematically would require hp & torque numbers, primary and tranny ratios, plus some idea of true top speed potential...and you'd still have to do some experimenting. I'd ask the vendor who supplied the engine, then source at least 3 countershaft sprockets (the one suggested, 1 tooth larger & 1 tooth smaller). For your planned trip, I'd aim for gearing on the high side, most mph/1000rpm. Three key points: 17t is usually the c/s size limit, a single tooth change at the c/s is roughly equivalent to 2 at the wheel, there's a fair amount of "wiggle room" to allow individual preference. Countershaft sprockets are inexpensive, plus quick & easily changed-out. You could even bring an extra along for a specific section of the ride. Pure trial & error testing will get you there, it'll just take a few extra steps. That's all the more reason to get some serious miles on the bike. Get it right, and you'll enjoy the rewards of your prep efforts all the more.

As for wheel bearings, the best sealed bearings made will dent your wallet by a whopping $35 over a set of cheapies, talk about inexpensive peace of mind. Koyo, NTN and F.A.G. (Germany) all make excellent quality "2RS" (2-side, rubber sealed) bearings.

A couple of oversights from my last post: spare inner tube & clutch cable. These are small & lightweight items that can leave you stranded. I've had zero luck with chinese clutch cables, the ends eventually pull off, and now strictly make my own. A failed clutch cable, 10 miles from home, sucks; I'd hate to think about having to deal with this 125 miles in-between "No" and "Place".

[chuckklr04]

Parts and more parts!

Working on the build.

Shopping Cart ItemOptionsUnit PriceQty.Cost TIRE_400x10 CHENG_SHIN 4_ply_rating $22.502 $45.00 INNER TUBE 350/400x10 $5.992 $11.98 4_SPEED_TRANNY GEAR_&_SHAFT_SET: SPROCKET FRONT 70's CT C ATC XL SL CL TRX ETC. SIZE_12T_TO_17T FITS_17MM_SHAFT

• #_OF_TEETH : 17T___(209P)75mm_OD

$7.971 $7.97 Wheel Bearings and Seal Kit CT70 & CT110 ALL_SL70'S ALL_XL70'S (3D)

• Choose : REAR

$15.992 $31.98 UNIVERSAL AFTERMARKET REAR SHOCKS pick LENGTH

• PICK_YOUR_LENGTH : 365mm_TOP_EYE_12MM_BOTTOM_10MM

$72.991 $72.99 REAR_SPROCKET 35/36/38/44 AND_46_TOOTH CT70_ATC70 TRX70_SL70 XL70_CL70

• TEETH : 35T____(14D)

$15.991 $15.99Subtotal: $185.91Shipping: $28.17*Tax: $0.00Total: $214.08

[chuckklr04]

How do I switch from an auto clutch handle bar to manual?

Looked around a bit on the net, but can't figure out the best way to do it.