Outa check & please do vote in the following thread, I've been hoping to get a good overview - but it does get overlooked from time to time lol;
Commuting or Cruising?
Noob Needs some Advice
- Thread starter Slogger
- Start date
Commuting or Cruising?
I voted fair weather, BA.
Today I was reading about DAX engines on other threads, pro and con, etc.
I ordered a 50cc to keep things mellow. Since there was some criticism of DAX I decided to check my head torque, it was about 15/16 ft lbs. Took off the head and measured the bore and stroke.. My engine has a 48mm bore and a 38mm stroke. I'm the owner of a 68.76 cc ht. I guess they thought I was making a bad choice going for the 50 because I'm a big dude, or maybe the 50's are not easily found anymore, after all, most people will automatically go for the 'bigger' engine. There is no head gasket, but the surfaces look good enough not to really need one, also the head has a lip that fits into the cylinder by maybe .8 mm or so.
I guess I'll reinstall the head, torque it to about 12 ft lbs and enjoy the displacement. I kinda wanted a 50, though.
One other thing, the cylinder wall hasn't been crosshatched. It's chromed.
No wonder it takes 3 tanks of gas to seat the rings.
Today I was reading about DAX engines on other threads, pro and con, etc.
I ordered a 50cc to keep things mellow. Since there was some criticism of DAX I decided to check my head torque, it was about 15/16 ft lbs. Took off the head and measured the bore and stroke.. My engine has a 48mm bore and a 38mm stroke. I'm the owner of a 68.76 cc ht. I guess they thought I was making a bad choice going for the 50 because I'm a big dude, or maybe the 50's are not easily found anymore, after all, most people will automatically go for the 'bigger' engine. There is no head gasket, but the surfaces look good enough not to really need one, also the head has a lip that fits into the cylinder by maybe .8 mm or so.
I guess I'll reinstall the head, torque it to about 12 ft lbs and enjoy the displacement. I kinda wanted a 50, though.
One other thing, the cylinder wall hasn't been crosshatched. It's chromed.
No wonder it takes 3 tanks of gas to seat the rings.
Last edited:
One thing was a guy said his head was over-tightened and cut thru the head gasket- I don't have one of those.
Another was something about the bearings in the piston (I didn't go that far in)
Actually, I'd say the little gem looks clean, well put together and ready. The castings all look fine, smooth, no voids or cracks or bumps. The only two allen heads are in the upper cases, the rest of the screws are pure china girl.
It is a 69cc, though, and was supposed to be a 50, so there is a little discrepancy there.
Since I ended up going with the hub adapter's 40 tooth (instead of the planned 48) the extra low-end power will be welcome.
I ain't mad about it, just noting that it wasn't quite what I ordered. I'll reserve my final opinion until I get to fire it up and ride it a little bit. I have very little experience riding these, I built one for my boss and got a few minutes on it, and a buddy built one that I took a short ride on, so I don't have much to compare it to. I'm pretty sure it'll be ok.
Another was something about the bearings in the piston (I didn't go that far in)
Actually, I'd say the little gem looks clean, well put together and ready. The castings all look fine, smooth, no voids or cracks or bumps. The only two allen heads are in the upper cases, the rest of the screws are pure china girl.
It is a 69cc, though, and was supposed to be a 50, so there is a little discrepancy there.
Since I ended up going with the hub adapter's 40 tooth (instead of the planned 48) the extra low-end power will be welcome.
I ain't mad about it, just noting that it wasn't quite what I ordered. I'll reserve my final opinion until I get to fire it up and ride it a little bit. I have very little experience riding these, I built one for my boss and got a few minutes on it, and a buddy built one that I took a short ride on, so I don't have much to compare it to. I'm pretty sure it'll be ok.
I've been considering omitting the tensioner. Then again, every motorized bike I've seen had one on it. I have decided on a compromise- I'm going to put a sprocket type with bearings on the original mount for now. This winter I'll design a new mount that clamps to the seat stay and chain stay so it can't get loose and fall off so easily.
I will plastidip the one included in the kit so it has more friction against the tube and loc-tite it real good, then check it every ride. If it's long enough I intend to hang it from the seat stay which will put gravity on my side.
Tomorrow I'll finish up the engine paint and begin the new fender brackets. I'm getting anxious to get started on the install, but the prep work, (like fender mounts) keeps holding things up. I don't have much time in the day to work on it, but I knew that going in.
My question for ya is, how would you cope with the continuing stretch of the chain without a tensioner? Just wait til it is loose enough to take out a link?
It would be easier to pedal without the drag of the tensioner and that is important to me, since I have a bum leg.
Many thanks to you and Crassius and everyone else that make this forum such an asset to wannabe motorized bicyclists everywhere.
The builds I have done without a tensioner were easy to adjust by simply shimming the rear motor mount to adjust chain length.
Cut a few thin shims and it's easy to take up the small amounts of slack that wear brings.
A better way to secure your tensioner would be a strap running between the rear stays top to bottom with the idler mounted in a slot.
This prevents it turning into the spokes and destroying your wheel.
Cut a few thin shims and it's easy to take up the small amounts of slack that wear brings.
A better way to secure your tensioner would be a strap running between the rear stays top to bottom with the idler mounted in a slot.
This prevents it turning into the spokes and destroying your wheel.
Thanks for the info, Maniac- I wrote a complicated reply and realized it was going in circles, but I will consider the shims. I lean toward just going with the standard setup for now, since it's so late in the season and my bike is in pieces all over the garage. I could run it without one if I could cut the chain just so... Too short and it's off to buy another chain.
Last edited:
I use a bike chain from Walmart, it's their "single" speed chain. Also purchased a chain break and u can easily shorten and lengthen ur chain by removing and install links. With a little finesse and practice.
Here's a page with some decent brackets for the idler cog, especially the 'arches' about half way down.
http://custommotoredbicycles.com/parts_for_motorized_bicycles_9_chain_tensioners_spring_loaded_chain_tensionerswhite_idler_wheel_415_chains
AG- You are using a bicycle chain on the engine? I'da never thought it would take the load of the engine power.
http://custommotoredbicycles.com/parts_for_motorized_bicycles_9_chain_tensioners_spring_loaded_chain_tensionerswhite_idler_wheel_415_chains
AG- You are using a bicycle chain on the engine? I'da never thought it would take the load of the engine power.
yeah im still using what ever came on the bike for pedal chain. and bell single speed chain for drive chain.
Bell single speed bicycle chain, huh..
That has to be lighter and easier to pull than 415 chain. Now ya went and made me think about using light chain to make the bike a little easier to pedal by leg power.
I would have guessed it would stretch out real fast and bind on the cog or something. If it would hold up, though-
How many miles would you guess that chain has been on there?
That has to be lighter and easier to pull than 415 chain. Now ya went and made me think about using light chain to make the bike a little easier to pedal by leg power.
I would have guessed it would stretch out real fast and bind on the cog or something. If it would hold up, though-
How many miles would you guess that chain has been on there?
As I posted earlier , nearly 100o miles. I keep it well oiled and stay on top of tension. I'm 250# and the same chain has been on two different bikes. 20 miles a day
I got it finished up and took it for a very short ride.. It started right up and 4 stroked on down the street. It is very quiet, needs some carb tuning and a bit of cleaning and touch-up, and I'll be done. At partial throttle, burbling along I looked down and was going 17.2 mph. It sounded like it was idling. This thing is going to have a little speed once it's broken in some and leane out. I mixed some 25 to 1 with valvoline 2 stroke oil but I don't really see any smoke. Hope that's normal..?
Thanks to everyone contributing on this thread, I appreciate all of your input and help!
Ahhh, life's good. Maybe I can go back to playing some guitar now. I haven't touched it since the engine got here.
[/url] 20mb image hosting[/IMG]
[/url] image upload no limit[/IMG]
It is very quiet, needs some carb tuning and a bit of cleaning and touch-up, and I'll be done. At partial throttle, burbling along I looked down and was going 17.2 mph. It sounded like it was idling. This thing is going to have a little speed once it's broken in some and leane out. I mixed some 25 to 1 with valvoline 2 stroke oil but I don't really see any smoke. Hope that's normal..? Thanks to everyone contributing on this thread, I appreciate all of your input and help!
Ahhh, life's good. Maybe I can go back to playing some guitar now. I haven't touched it since the engine got here.
Last edited:
