the cable can be extended by using the proper gauge wire and making clean connections...mine is ordered, the free shipping is UPS ground so i guess this could take a while. shoot, i was hoping they popped it in a USPS envelope, i'd have it in just a coupla days.
TREK 4500/ GEBE w/ GP460 build
- Thread starter DetonatorTuning
- Start date
DetonatorTuning
Active Member
the pickup cable can be lengthened with copper strand wire ?
they are 90 mls. from me, i'll see how long it takes them to get one here.
thanks,
steve
A
appye
Guest
Hi there! The other day I did something really stupid and burned my Tanaka 32cc GEBE engine by not putting in enough oil to the mixture. I wanna kick myself. Really hard. Anyway, I took the thing apart and the cylinder is completely shot and I am looking at probably in the neighborhood of $150 to repair it. Too bad, I even bought the HP carb and only put about 100 miles on it before burning up my engine with my stupidity, moronicism, dumbness, retardation, aaaaaaargh! ...you get the idea.
Anyway, are these davesmotors.com engines a drop in replacement for my tanaka? Where else can I find motors that will bolt right up to a GEBE kit? What do I look for? Is it okay, so long as it is using the 76mm clutch? I am interested in getting a stronger motor. Ideally, I would like to be able to do 45mph on the flats and still get 100+ mpg. Is this engine feasable? 4.2hp seems a bit much for the GEBE kit, as I dont' want to break things with too much power. Maybe one of the smaller engines in the 3 hp range? I don't so much mind having to learn how to finesse the throttle to keep things from breaking. How loud are they in comparison to the Tanaka? My mind is racing ...
Anyway, are these davesmotors.com engines a drop in replacement for my tanaka? Where else can I find motors that will bolt right up to a GEBE kit? What do I look for? Is it okay, so long as it is using the 76mm clutch? I am interested in getting a stronger motor. Ideally, I would like to be able to do 45mph on the flats and still get 100+ mpg. Is this engine feasable? 4.2hp seems a bit much for the GEBE kit, as I dont' want to break things with too much power. Maybe one of the smaller engines in the 3 hp range? I don't so much mind having to learn how to finesse the throttle to keep things from breaking. How loud are they in comparison to the Tanaka? My mind is racing ...
DetonatorTuning
Active Member
i'm going to defer to augidog for a clear answer of what other engines will work with the GEBE kit originally intended for the Tanaka 32cc. not sure but, i think the clutch size is going to be the main factor.
i have recently learned that there are more than one "U" strap main mounts and the engine specific kits each have the one that fills it's need.
the Tanaka engines are pretty legendary, along with the likes of Zenoah etc.
are the Chung Yang clone motors their equal ? i can't say, i haven't had either of the others and only had my GP460 for 2 weeks.
it may prove out that the GP460 in stock configuration is all the GEBE system can take. it might be that we can use a pipe and hot ignition too. don't know for sure yet.
my problems seem to be related to the 3000rpm springs i chose to start with. i need to have springs that will let go pretty quick after i let off the gas, but not at 8100rpm like the stockers. it's going to be a compromise and then i'm going to have to finesse it as you say.
good luck,
steve
i have recently learned that there are more than one "U" strap main mounts and the engine specific kits each have the one that fills it's need.
the Tanaka engines are pretty legendary, along with the likes of Zenoah etc.
are the Chung Yang clone motors their equal ? i can't say, i haven't had either of the others and only had my GP460 for 2 weeks.
it may prove out that the GP460 in stock configuration is all the GEBE system can take. it might be that we can use a pipe and hot ignition too. don't know for sure yet.
my problems seem to be related to the 3000rpm springs i chose to start with. i need to have springs that will let go pretty quick after i let off the gas, but not at 8100rpm like the stockers. it's going to be a compromise and then i'm going to have to finesse it as you say.
good luck,
steve
A
appye
Guest
hmmm. I have read through this thread and I don't quite understand what you mean by the springs releasing too quickly. I don't mind going through brake pads and not using the engine to slow me down if that is what you mean ... What exactly does this cause to happen with this "too quick" release that occurs? I could see why you wouldn't want them to engage too quickly, but release? Sorry, I am a bit new to this. Also, I could also just use the spring (or even the entire clutch?) from my Tanaka to make this work the way it does straight from GEBE.
DetonatorTuning
Active Member
appye,
i'll try to make the situation a little more clear.
the centif. clutch in these engines has what are called shoes (or pads ) that are held in line and position by alignment by solid metal "ramps "
in order for the negine to start and idle the shoes have to be held back away from the clutch bell, to do this there are springs attached across the shoes, or you would have fulltime drive.
the springs themselves can be made of differing wire dia., # of coils and free length in order to control when the shoes start to respond to the expantion force and start "driving "
the rpm range that the spring controlled shoes start to engage and "drive" is the same rpm that they will let go and freewheel the drive.
now these engines in general are all pretty much designed for uses where they have very little operational load and very nearly NO off throttle induced " engine braking " or tortional back pressure. off the gas, the clutch lets go and it's idling, faster than it took to type this.
now to be successful , you need to know when your clutch is going to engage and let go in relation to the ground speed and engine rpm range you want to operate in.
the problems arise when say, you wish to move 25mph and your clutch is going to be slipping and heating up at anything under 8100rpm. in this case, you will have to A) use more rpm's (which will make you go faster too ) or B)use lighter springs in the clutch so that you are fully engaged at that speed.
if you went with A) you would travel faster and when you let off the gas the engine would return to idle pretty quickly.
B) would have you doing 35mph, but when you let of the gas the clutch would stay engaged longer thru the decelleration process and be causing the negatives of "reverse torsion, engine braking " until it lets go.
Ssssoooooooooo, when i use 3000rpm springs that will literally take hold and start "driving" with no problems from under 10mph and i'm traveling 35+mph at 1/2 throttle (9000rpm) then release the throttle, the clutch is going to stay engaged and transferring the reverse stress of deceleration thru the drive system and ultimately to the "weakest link" which in my case is the belt until i'm going 10mph when the engine is no longer being "driven" at a speed above 3000rpm.
at this point, you would think that the solution is to use heavier, higher rpm engagement springs, and to a point that's true and i will be.
lets say i have 8100rpm springs and i'm using 1/2 to full throttle on my commute between towns, alls good, when i need to make a turn or stop i just let off, coast down enough to make the transistion and resume.
but, when i get into town and i need to do 25mph, the clutch will be slipping and heating up at anything under 8100rpm at which point i'll be going atleast 35mph again because this is a single speed drive arrangement.
all of these problems are due SOLELY to trying to use more engine, rpms and ground speed than most people intended or invisioned in the design and production of these 2 stroke kits in general.
for me, in the end, i will learn to work thru all this , OR i will convert to a mechanical clutch to relieve the negatives and allow me to keep the belt.
this is now pretty long and l have likely muddied the water even further. i hope you have gotten some good from it AND that other more experienced members will give their insights and correct the things i have confused.
steve
i'll try to make the situation a little more clear.
the centif. clutch in these engines has what are called shoes (or pads ) that are held in line and position by alignment by solid metal "ramps "
in order for the negine to start and idle the shoes have to be held back away from the clutch bell, to do this there are springs attached across the shoes, or you would have fulltime drive.
the springs themselves can be made of differing wire dia., # of coils and free length in order to control when the shoes start to respond to the expantion force and start "driving "
the rpm range that the spring controlled shoes start to engage and "drive" is the same rpm that they will let go and freewheel the drive.
now these engines in general are all pretty much designed for uses where they have very little operational load and very nearly NO off throttle induced " engine braking " or tortional back pressure. off the gas, the clutch lets go and it's idling, faster than it took to type this.
now to be successful , you need to know when your clutch is going to engage and let go in relation to the ground speed and engine rpm range you want to operate in.
the problems arise when say, you wish to move 25mph and your clutch is going to be slipping and heating up at anything under 8100rpm. in this case, you will have to A) use more rpm's (which will make you go faster too ) or B)use lighter springs in the clutch so that you are fully engaged at that speed.
if you went with A) you would travel faster and when you let off the gas the engine would return to idle pretty quickly.
B) would have you doing 35mph, but when you let of the gas the clutch would stay engaged longer thru the decelleration process and be causing the negatives of "reverse torsion, engine braking " until it lets go.
Ssssoooooooooo, when i use 3000rpm springs that will literally take hold and start "driving" with no problems from under 10mph and i'm traveling 35+mph at 1/2 throttle (9000rpm) then release the throttle, the clutch is going to stay engaged and transferring the reverse stress of deceleration thru the drive system and ultimately to the "weakest link" which in my case is the belt until i'm going 10mph when the engine is no longer being "driven" at a speed above 3000rpm.
at this point, you would think that the solution is to use heavier, higher rpm engagement springs, and to a point that's true and i will be.
lets say i have 8100rpm springs and i'm using 1/2 to full throttle on my commute between towns, alls good, when i need to make a turn or stop i just let off, coast down enough to make the transistion and resume.
but, when i get into town and i need to do 25mph, the clutch will be slipping and heating up at anything under 8100rpm at which point i'll be going atleast 35mph again because this is a single speed drive arrangement.
all of these problems are due SOLELY to trying to use more engine, rpms and ground speed than most people intended or invisioned in the design and production of these 2 stroke kits in general.
for me, in the end, i will learn to work thru all this , OR i will convert to a mechanical clutch to relieve the negatives and allow me to keep the belt.
this is now pretty long and l have likely muddied the water even further. i hope you have gotten some good from it AND that other more experienced members will give their insights and correct the things i have confused.
steve
A
appye
Guest
Thanks for the explanation. I understood completely actually and the waters are not muddied at all. I wonder if there is some way to have a "hybrid" mechanical/automatic clutch? If there is then one would probably go with a low RPM autoclutch and have the manual clutch hooked into the brakes or something... I have worried about this myself with my Tanaka 32cc on my daily commute to work for a somewhat different reason. I did not like the fact that I would be coasting downhill for a good 3 mile stretch every day with the engine engaged at 30+ mph. I did not like this because a 2-stroke is lubricated by the application of fuel into the system, so coasting downhill with the engine screaming at full speed would theoretically inhibit proper lubrication. This fear may be unfounded though, I am not sure.
Also, I am wondering why deceleration would put stress on the belt. I see you did things to make your tension arm move more smoothly. I have done similar things and it is the arm that always caused my belt to slip. I ride a recumbent and am pretty much always reaching back and pulling back on the lever while riding. It gets a little loose after downhill or speedbumps, even from uneventful flatland riding after a while. So I am wondering if perhaps your belt is getting chewed up because of that? I have never really liked the design of this arm too well.
I have been thinking of grabbing a few different belt tensioners from a junkyard and seeing if they might work better. Or perhaps I can think of a way to have it mounted and riding on an actual bearing instead of getting caught up on the threads of a bolt or stud like it is now. I can't make it too tight because it won't move, but too loose and the arm gets cocked where it is not perfectly parallel to the tension bracket...
Hmmm. Any idea what the formula is to show what RPM is needed for a specific speed using the #14 gear on a GEBE setup? I want to know what I am looking at for speed when I am browsing engines ... perhaps someone has made a chart somewhere?
Also, I am wondering why deceleration would put stress on the belt. I see you did things to make your tension arm move more smoothly. I have done similar things and it is the arm that always caused my belt to slip. I ride a recumbent and am pretty much always reaching back and pulling back on the lever while riding. It gets a little loose after downhill or speedbumps, even from uneventful flatland riding after a while. So I am wondering if perhaps your belt is getting chewed up because of that? I have never really liked the design of this arm too well.
I have been thinking of grabbing a few different belt tensioners from a junkyard and seeing if they might work better. Or perhaps I can think of a way to have it mounted and riding on an actual bearing instead of getting caught up on the threads of a bolt or stud like it is now. I can't make it too tight because it won't move, but too loose and the arm gets cocked where it is not perfectly parallel to the tension bracket...
Hmmm. Any idea what the formula is to show what RPM is needed for a specific speed using the #14 gear on a GEBE setup? I want to know what I am looking at for speed when I am browsing engines ... perhaps someone has made a chart somewhere?
Last edited by a moderator:
DetonatorTuning
Active Member
great, i always wonder if i come across as just rambling without ever getting anywhere.
on the surface, the "hybrid" system is a CVT, IF you can configure the correct setup and make it live. this is being done by several members here.
i don't think the issue of coasting with the engine engaged is about internal lube. the engine is running and therefore getting lubed.
my issue with coasting down against the engine is not knowing what kind of damage it might be doing to the bearings etc. i'd love for someone to give some input on those possibilties, real or imagined ?
AND the fact that in decel mode with the clutch still in engagement the wheel is causing the belt to pull down ON THE FRONT of the drive cog, which causes the arm to open, relieving the tension and allowing the belt to be drug around the bottom of the drivering, stressing or removing the teeth. when the clutch is disengaged and freewheeling none of this happens.
in drive function the belt is pulled forward over the BACK of the cog, creating lax tension in front where the arm is there to take it up and keep the belt tight around the drivering.
as for the arm, i now have mine in an adjustment plain that keeps the arm parallel with the mount bracket and thus the bearing square with the belt.
you could also cut a slot in the bracket and put the bearing on an internally threaded post/ stud coming out thru the slot and use a captive bolt to adjust the bearing back and forth. nice, but not spring loaded anymore, so you would loose the quick disconnect feature of the current arrangement.
i can tell you that with my GP460, that at 35+ it's turning about 9000rpm w/ the 14T cog.
steve
on the surface, the "hybrid" system is a CVT, IF you can configure the correct setup and make it live. this is being done by several members here.
i don't think the issue of coasting with the engine engaged is about internal lube. the engine is running and therefore getting lubed.
my issue with coasting down against the engine is not knowing what kind of damage it might be doing to the bearings etc. i'd love for someone to give some input on those possibilties, real or imagined ?
AND the fact that in decel mode with the clutch still in engagement the wheel is causing the belt to pull down ON THE FRONT of the drive cog, which causes the arm to open, relieving the tension and allowing the belt to be drug around the bottom of the drivering, stressing or removing the teeth. when the clutch is disengaged and freewheeling none of this happens.
in drive function the belt is pulled forward over the BACK of the cog, creating lax tension in front where the arm is there to take it up and keep the belt tight around the drivering.
as for the arm, i now have mine in an adjustment plain that keeps the arm parallel with the mount bracket and thus the bearing square with the belt.
you could also cut a slot in the bracket and put the bearing on an internally threaded post/ stud coming out thru the slot and use a captive bolt to adjust the bearing back and forth. nice, but not spring loaded anymore, so you would loose the quick disconnect feature of the current arrangement.
i can tell you that with my GP460, that at 35+ it's turning about 9000rpm w/ the 14T cog.
steve
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T
Torques
Guest
DetonatorTuning
Active Member
thank you sir ,but i'm just slightly embarased now that i didn't proof read that post alittle better !!
since you have been following the thread, you understand there is much more involved now then the simplicity of configuring the hardware.
would you like to add any other comments or insights please ?
thanks,
steve
since you have been following the thread, you understand there is much more involved now then the simplicity of configuring the hardware.
would you like to add any other comments or insights please ?
thanks,
steve
