Honda gxh50 compared to clones?

[HoughMade]

I run the Honda GXH50 with the Grubee Skyhawk II and a 48 tooth sprocket. I don't have a tach and I could run the numbers, but frankly...it's been a long day.

I easily cruise at 25 mph. In fact, the engine seems happy at that speed or slightly higher. It even feel like I'm holding it back a little at 25. It will do 30 mph easily, but I would not run it all day at that. Top speed is over 35 mph and I would say approaching, at or slightly above 40- but I would not want to run that for long. I do not have a governor on the engine and I suspect that at 40, it is revving faster than it probably should be...but it will do it.

 

[Irish John]

My engine is a HuaSheng FG 142 with Grubee 2nd generation GB
Bike is a Schwinn Alloy Seven Cruiser with a 48T sprocket
I weigh 92 kilos (my winter weight!)
My bike has a top speed on the flat of 32.31mph but I wouldn't stay there for more than a moment.
I cruise at 25 - 27 mph
My speedo should be accurate cos the computer input setting was the measured tyre circumference with me on the saddle.
With gears these engines will achieve great speeds cos I've done it using a smaller sprocket hitting 40 mph max.

 

[MotorbikeMike]

Poster Child, 4-stroke of the month

HI all, well today I fired up the little HS/JL it had a bad clanging noise that I was hoping was in clutch/gearbox area, not the crankcase.
Here are pics. Well one point of interest is that the clutch hub is made of tin, which is entirely inadequate. The little engine sounds very good, but unless I make a shim of some sort to bring the output shaft up to 5/8 I will not be able to test this engine's performance nose to nose with the Honda.

I will mount the Honda, test the orig muffler box, short (kit) pipe, and the Long Pipe I bought. After testing the performance of the pipes stock, I'll modify them and test.

I am happy that the output shaft is not damaged, like the one that I saw pics of that had blown out the key-way, what a bummer!

On with the test!

Mike

 

[cruiser66]

Hi Mike,

Hope you can adapt the HuaSheng to the Honda gearbox so that you can make a true comparison. I'm assuming that you have a Honda with the Grubee gearbox. They do sell the HuaSheng (142FG) model with the Grubee which has the same size output shaft as the Honda. The JL Hoot comes with the 142F.
That clutch bell sure is toast. Looks like you ran it dry or almost dry. My clutch bell (pictured on left) appears to be stamped steel. I also have, as a spare, the second generation JL Hoot which seems to have a slightly heavier clutch bell (pictured on right). I am still running the old Hoot with 75W90 with no problems. It's reasonably quiet, but the newer box is supposed to be better. I'll have to do my own comparison.

66

 

[MotorbikeMike]

Gearbox blues

Hi Cruiser, I never ran that box dry, I used Hypoid gear lube (stunk terribly and bubbled out all over everything), solid grease (clutch wanted to chatter, not staying wet, and it is a wey type clutch), and later the flesh-colored disk brake grease, with some 40 wt engine oil making a nice "slurry" that worked very well. The clutch hub should never been made of tin, and perhaps the design was flawed enough to let the shoes go in too deep, and therefore cut the rim off of the drum.

I have a Grube box, and a Honda...........AND a complete HS/JL kit which I will open to continue my testing. Since the early JL clutch is so weak, I would not feel right about selling that kit, so I will use it in testing.

Will the newer ckutch bell slide right into the early gearbox do you think?

Mike

 

[Irish John]

Cruiser, I have just got a HuaSneng & hoot kit. What should I run the gearbox on so the clutch doesn't slip and the engine stays good. Haven't found a frame yet to mount it on. It won't fit that many bike frames cos the tray isn't adjustale. Also it came with 44T sprocket but what is the best sprocket size for these kits?

 

[cruiser66]

Hi Cruiser, I never ran that box dry, I used Hypoid gear lube (stunk terribly and bubbled out all over everything), solid grease (clutch wanted to chatter, not staying wet, and it is a wey type clutch), and later the flesh-colored disk brake grease, with some 40 wt engine oil making a nice "slurry" that worked very well. The clutch hub should never been made of tin, and perhaps the design was flawed enough to let the shoes go in too deep, and therefore cut the rim off of the drum.

I have a Grube box, and a Honda...........AND a complete HS/JL kit which I will open to continue my testing. Since the early JL clutch is so weak, I would not feel right about selling that kit, so I will use it in testing.

Will the newer ckutch bell slide right into the early gearbox do you think?

Mike

I wonder if some of these clutches were defective to start with. I had to add a mod to stop the bubbling and leaking out the vent hole. The 36T sprocket I use stresses the clutch a lot more than the original 44T shipped with the kit, but there has been no unusual slipping or overheating. I use 75W90 synthetic oil. The newer clutch bell has angle cut teeth. I believe it will fit into the older box as long as you change the main gear. I did notice a variation of about 1/8" on the contact pattern between the the clutch pack and the bell depending on which way the clutch pack was mounted on the motor shaft. If the clutch was mounted backwards, it could account for the edge cutting the bell.

66

 

[cruiser66]

Cruiser, I have just got a HuaSneng & hoot kit. What should I run the gearbox on so the clutch doesn't slip and the engine stays good. Haven't found a frame yet to mount it on. It won't fit that many bike frames cos the tray isn't adjustale. Also it came with 44T sprocket but what is the best sprocket size for these kits?

Hi John,

I use 5 ounces of 75W90 gear oil. It would be worth your while to check the orientation of the clutch pack in relation to the bell. There have been problems with the clutch cutting through the bell and I think it could be because the clutch pack is installed backwards. Another fix could be to install a proper size washer between the bell and the clutch pack but then you would have to make sure the gear on the bell aligns with the main gear. My kit is installed on a 15 year old mountain bike with standard size straight tube framing. I would look in yard sales or other places where you might find a decent used one. I could barely break 22 mph with the 44T. I'm using a 36T which allows me to break 30 mph and still have decent hill climbing ability. I had to install an internal baffle to stop the oil from spraying out the fill plug vent hole.

66

 

[MotorbikeMike]

Grube gearbox keys

Hi all, well I got out the Grube box to put it on the Honda, and can you believe it? All the times I've worked with the Cheap China Kits, I never stripped any threads in a new engine, and my Honda has the upper inside mounting screw's threads badly made and they pulled out on me! Not overtightened, just bad from the gate!

No Worries, Mate, because as soon as I'm done comparing I do not intend to use the gearbox anyway, and it will surely hold on 3 bolts for my testing purposes.

Question for you guys that have had the Grube Box open, I got mine sideways, and they condition is new, but without the bolts, nuts, and keys. I'm ok with the nuts and bolts, but the keys......

In the HS the key was apparently hammered into the clutch, no set-screw, just pounded in. There was another glaring mis-calculation of correct mechanical function, when I found out that the clutch actually spins on the engine shaft, wearing it, this is an absolute No-No!!!

The Grube box has a seperate, apparently case-hardened piece that spaces the clutch from the hub (also case-hardened) and keys to the engine shaft, eliminating wear on the crankshaft spud.

Here is the question, is the cluutch, and the spacer in with one long key, or 2 short ones? I will make the cotton-pickin keys if I have to, but prefer to know how the orig was done. Are the keys "peened" in, or just slid on?

The Grube mount extends I'm told, how long is it extended, and compacted?

I need to figure out a new mount for what I'm wanting to do, and it would help if I knew the average of what was needed to be sucessful.

Has anyone done a more motor-bikey Air Cleaner?

Well I got to call it a night, tomorrow will be a new day, and who knows, it may hold some answers?

Mike

 

[Irish John]

Mike, That was bad about the Honda female thread stripping. Did you re-tap it with a 6mm tapper or did you have to go to a larger bolt size? I think they are 6mm dia. bolts or M6 I think they are called.
How did you go with the bolts that hold the tray to the aluminium sliders - I had one strip first time and 3 that stripped within 5 weeks so I used longer bolts with locknuts on the end. It is a really horrible job getting the nuts on in the tight spaces but at least the engine is secured properly. Then there are the 4no. 6mm dia. studs that hold the tray to the downtube and seat tube. They need to be remade in good steel and even then the whole stability of the motor is relying on steel threads into aluminium which is very inadequate. My two engines are both held with just those studs but really I should either drill the holes out and tap them for 8mm dia studs or preferably drill right through the aluminium and put nuts & washers on the end of those studs. The badly made clutch arrangement you refer to - is that a Grubee or Hoot GB? Sounds like a Hoot to me cos the grubee clutch doesn't spin on the shaft - it's keyed to the shaft. The Honda & HS /Grubee has 2 No. keys and they slide in - no need for hammering Mike. That's my understanding but I might have forgotten since I was last inside them both. I now have a Honda & HS with Grubees and also will have, in a few more days, a HS|Hoot kit. I do not expect to be very pleased with the Hoot - it looks like a lemon to me and I'm finding it hard to find a frame to host the engine tray cos it's a bit too short for a cruiser. The 10T fixed sprocket isn't a great idea either but time will tell.
I think you will find that the grubee needs a 50 or 52T sprocket to perform best. In fact I'm sure of it. I've had a problem trying to get a sprocket & clamping pads & brackets specially madeto fit my Schwinn Deluxe 7 and have produced drawings to see if Andy can make it for me. It's a problem I could do without but the Schwinn D7 is the best host available in Australia and I can't bring myself to throw out the 7spd geared hub on bikes costing $800 each - the hub costs $400. Anyway I attach the sprocket drawings in case they might help anyone.