How long has it been running?
I've seen ht's get better for hundreds of miles as they get fully broken in...
I've seen ht's get better for hundreds of miles as they get fully broken in...
Schwinn High Timber hi speed build
- Thread starter graydog8josh
- Start date
how many 50cc's do you have that go 35mph. I'll buy it from you for 150 if you can show it goes 35mph
I gotta say this thread is so much the same exact experience I have gone thru on my first build. I like Graydogs detailed descriptions and the same quest for a mile per hour goal Im going thru. Every 1/2 mph is big since it all adds up.
Keep on tuning.
Keep on tuning.
just switched back to a bgf 66cc with arrow reed cylinder. Was really really hard to start initially. and i can hear an air leak but i got it to start and idle. much much much faster than the 50cc. Its almost unbelieveable. the head got really hot really fast and i havent done a plug chop yet. I think its too lean
you should be hitting much higher speeds with that setup! Are you sure its not 4 stroking or running too lean? 72 does sound like kind of a big jet. How is your compression?
Status update:
The engine:
Unmodified 50cc bgf motor
Z pipe intake with:
NT carb: #70 jet, clip in second position
Exhaust:
torquer 2 pipe
Ignition:
stock with jaguar spark plug wire
BP6HS plug
Fuel:
3.0L gas tank(the one with m6 mounting bolts, nice...)
Scoot city 36:1 oil mix
Drivetrain:
Kings 34T sprocket
Skipdu spring tensioner
24" wheel 1.75 cheng shen street tire (rear)
26" wheel 2.0 Specialized 'The Captain' tire (front)
cruising speed: ~21-25mph
top speed: 28 mph
it seems to be able to pull me from about 7 or 8 mph up to 25 on flats.
I just ordered the arrow 4.5 street racer engine so we'll see what difference that makes
The engine:
Unmodified 50cc bgf motor
Z pipe intake with:
NT carb: #70 jet, clip in second position
Exhaust:
torquer 2 pipe
Ignition:
stock with jaguar spark plug wire
BP6HS plug
Fuel:
3.0L gas tank(the one with m6 mounting bolts, nice...)
Scoot city 36:1 oil mix
Drivetrain:
Kings 34T sprocket
Skipdu spring tensioner
24" wheel 1.75 cheng shen street tire (rear)
26" wheel 2.0 Specialized 'The Captain' tire (front)
cruising speed: ~21-25mph
top speed: 28 mph
it seems to be able to pull me from about 7 or 8 mph up to 25 on flats.
I just ordered the arrow 4.5 street racer engine so we'll see what difference that makes
waiting for the arrow 4.5 to come in the mail.
I tried putting the reed kit on last night and i dont have enough frame clearance to get it to fit. Need to extend the intake. Right now i dont have enough frame clearance to run the stock intake either. I have the z pipe hooked up. Might try going to a hardware or auto parts store today to try to find some heater hose to extend the intake.
What size heater hose is the right size for the intake on these engines?
does the hose go over where the clamp is, or would it be better to run a copper pipe out of the intake and clamp the hose on that? this is what im thinking
I dont know if anyone else has tried to run reeds without making additional transfer ports or tried to run reeds on a z50 but its worth a try. This motor has run well so far.
I tried putting the reed kit on last night and i dont have enough frame clearance to get it to fit. Need to extend the intake. Right now i dont have enough frame clearance to run the stock intake either. I have the z pipe hooked up. Might try going to a hardware or auto parts store today to try to find some heater hose to extend the intake.
What size heater hose is the right size for the intake on these engines?
does the hose go over where the clamp is, or would it be better to run a copper pipe out of the intake and clamp the hose on that? this is what im thinking
I dont know if anyone else has tried to run reeds without making additional transfer ports or tried to run reeds on a z50 but its worth a try. This motor has run well so far.
Attachments
Im not sure what the ID of the hose im using is for my intake, but its just regular HD washing machine hose and it works greAt
Just slapped on the #41 chain i had laying around and it is so so much smoother than the kit chain. I rode around yesterday reaching speeds of 29mph averaging about 25 when fully warmed up. It was a nice journey to go get ethanol free gas about 20 miles round trip and took some pictures of me around town and on campus. When i got home i noticed my chain was tracking off to the side and i happened to look down to see one of the rivets holding the chain together was pushed out to one side. one of the outer side plates wasn't even connected. I think if i would have rode around like that i would have surely popped that chain.
My motor ships saturday according to dave rust. I think with using the 41 chain like he said i will not tear things up wiht that 4.5 hp beast im adding to the mix. Excited.
My motor ships saturday according to dave rust. I think with using the 41 chain like he said i will not tear things up wiht that 4.5 hp beast im adding to the mix. Excited.
Attachments
Last edited:
#41 chain, so so smooth.
Also im posting some of the other pictures i took on my 20 mile ride to get ethanol free gas.
Also im posting some of the other pictures i took on my 20 mile ride to get ethanol free gas.
Attachments
In preparation for my 4.5 horsepower arrow motor:
Basically going to swap the 50cc for the 66cc arrow.
I dont anticipate any problems.
I know my redline will be bumped up from 5k to above 7k, and ill have to figure out how this thing works with the different carb.
at 7k my top speed should be ~35
at 5k my speed should be about 25
I guess ill start out with the richer jet and then lean it out, since my break in mix will be pretty lean initially anyway. 16:1
The moment it comes in the mail ill take photos and try to do like a time lapse of the bike coming apart and then coming back together. That way if im doing somethign wrong, it will be blatantly obvious. I also plan to collect a lot of speed data and give descriptive details of how much of an improvement i see. I remember my dax 66cc being quite the rumbler and i was amazed at how smooth the 50 was. Ill try to compare the harshness of the higher powered motor.
i feel like im missing some important information...
Ultimately i hope the addition of this motor brings forth my skill as a builder of a reliable Schwinn hi timber and re-establishes the high speed mark i set for myself of mid 30's sustained.
Im not going to change the 34T sprocket unless i can figure out how to keep my chain from rubbing the frame.
I paid 510 for this motor, so I feel i should be as in depth as possible in assessing it. Im sure many people are on the fence about whether this would be a good investment for them. I believe that dave rust is doing great things with these little motors and I hope that my purchase helps advance the development of this motor.
If anyone has any suggestions or ideas please feel free to share, ill be bugging people to make sure i collect the right kind of data the audience wants to see.
I mean, do you want to see charts, pictures, videos?
What kind of information do peopel want to know.
Also wingnut has one of these motors too, he helped me decide to make this purchase.
Basically going to swap the 50cc for the 66cc arrow.
I dont anticipate any problems.
I know my redline will be bumped up from 5k to above 7k, and ill have to figure out how this thing works with the different carb.
at 7k my top speed should be ~35
at 5k my speed should be about 25
I guess ill start out with the richer jet and then lean it out, since my break in mix will be pretty lean initially anyway. 16:1
The moment it comes in the mail ill take photos and try to do like a time lapse of the bike coming apart and then coming back together. That way if im doing somethign wrong, it will be blatantly obvious. I also plan to collect a lot of speed data and give descriptive details of how much of an improvement i see. I remember my dax 66cc being quite the rumbler and i was amazed at how smooth the 50 was. Ill try to compare the harshness of the higher powered motor.
i feel like im missing some important information...
Ultimately i hope the addition of this motor brings forth my skill as a builder of a reliable Schwinn hi timber and re-establishes the high speed mark i set for myself of mid 30's sustained.
Im not going to change the 34T sprocket unless i can figure out how to keep my chain from rubbing the frame.
I paid 510 for this motor, so I feel i should be as in depth as possible in assessing it. Im sure many people are on the fence about whether this would be a good investment for them. I believe that dave rust is doing great things with these little motors and I hope that my purchase helps advance the development of this motor.
If anyone has any suggestions or ideas please feel free to share, ill be bugging people to make sure i collect the right kind of data the audience wants to see.
I mean, do you want to see charts, pictures, videos?
What kind of information do peopel want to know.
Also wingnut has one of these motors too, he helped me decide to make this purchase.
I am looking forward to hearing about the Arrow build, I considered doing a piston port reed from them but decided to order a KTM clone instead.
noooooo! not 16:1 try 24-1. the sha carbs are stupid easy to tune. I'd recommend going to treatland.tv and buying this: https://www.treatland.tv/dellorto-main-jets-60s-range-p/dellorto-main-jets-range-60s.htm
when i ran a SHA with this setup below I used a 64-5 jet and it was perfect - never hit 400 degrees and was not 4 strokey.
when i ran a SHA with this setup below I used a 64-5 jet and it was perfect - never hit 400 degrees and was not 4 strokey.
had to cut down the rear mount to get the motor to fit in the frame. These brackets are a lot beefier than the ones that ive gotten before. I didnt take a side by side comparison yet, but the head is 2/3's the side of the cylinder
Attachments
cranked it for the first time today. It may be because im still running nt carb but the powerband is super narrow. I also had to change to 26" wheel 36t sprocket. I dont want to go stock sprock because i have frame clearance issues. I feathered the clutch an little and was able to come off a dead stop and then at about 17 it just starts flyin. Its dark now so i didnt give it the beans yet but it is definitely moving. Ill check tommorrow if i can go 35 then mission accomplished! I'll have to start a new thread.
I recently came by a couple of bottles of a 50:1 synthetic oil. I'm not planning on using it anytime soon, but once my engine is finished breaking in, should i use these or is it wayyyyyy to lean?