new 4 stroke kit screaming

[adventureluck]

I put this kit Gas Bike Storm 49cc 4 Stroke Bicycle Motor - Gas Bike Storm 49cc 4 Stroke Bicycle Engine Kit on my bike. There is plenty of oil in the oil tank, the correct gas in the gas tank. I idled the bike for at least 10 minutes and it sounds great. When I try and ride it the gearbox screams twice as loud as the engine. The damn chinese (no offense to any race, just the people working there) tore the heads on the screws holding the gearbox together so I can't even unscrew it. Any idea why there would be loud 10k rpm kawasaki ninja like screaming coming from the gearbox when I run this thing? Or would it be something else. Is this normal? Never CHINESE AGAIN! It sounds awesome if I rev the engine a bike while I'm sitting and the gears in the gearbox aren't turn but as soon as I start moving forward I hear all this squealing. I'm going to see if I can get to a lowes or something for them to get that stuck screw out. And maybe put in new gears or I dunno anything!

 

[Dan]

Sorry to hear you have ran into this.

 

[glacknoid]

I would toss the hoot gearbox in the garbage and keep the rest. If you payed 250 for all of it that's not a bad deal the motor with all the other parts seperately are worth more than that. Go to bicycle-engines.com and get a grubee skyhawk stage 3 complete gearbox for 119 and you will be good to go. Or wait till the grubee's 4g belt drive becomes available soon on the same web site and you won't hear a thing but the motor.. It's a new belt drive system that's quiet as a mouse. There are some other american made gearbox's out there but you'll have to spend a lot more. If that's cool ez motorbikes I hear has a sweet setup soon to hit the market. also one from firebelly looks like a great option Check out some of the other threads that feature more info under the 4-stroke catagory. Even the grubee skyhawk stage 3 makes some noise I'm sure it's not as bad as the one that came with your kit.

 

[MotorbikeMike]

Hi Adventure, yes those boxes are noisy, some more than others. My Hoot lasted about 50 miles before it cut the clutch-bell in half, effectively making the whole thing useless/

It was then I saw a need, and a few months later, www.ezmotorbikes.com was born, with the "Silent Power" transmission system. This has proved to be the best solution to the noise, AND long lfe, with the unexpected bonus of more usable HP from the engine.

Mike

 

[adventureluck]

Have any links? What gearbox is more reliable/quieter? Will they go on my engine?

 

[adventureluck]

Also how can I get the gearbox off? I unscrewed all the screws on the box and I still can't even get the top of it off. But yah this gearbox suxors and I'm glad yer helping me figure it out.

 

[adventureluck]

I read this in another forum -

The gear box included in this kit is NOT the same as the Grubee gear box. Grubee actually has a patent on his design. The HuaSheng engine output shaft is too short for this gear box clutch design. This means that you have to use several flat washers to make the shaft longer. This is causing the bell housing to split and fail after a short amount of use.
2) The gearbox is not compatible with the Honda GXH 50.
3) The gearbox does not include an engager system.
4) The gearbox includes a fixed rather than a freewheel output sprocket.
5) The kits are sold with no warranty from the factory. This means it is up to the vendor to stand behind their product. I tried to follow the instructions to submit a warranty issue with one of the vendors and the web form I was supposed to use did not exist.
6) To my knowledge there is currently no way to obtain parts for this kit. If you break something I guess you’ll need to buy a whole new kit.
7) The mounting plate is not adjustable which limits the bikes the kit will fit.
8) Does not include the dual brake, throttle, kill switch grip.
9) Does not include a kill switch. You must purchase and install your own.

 

[MotorbikeMike]

Ok, once the screws are removed, the outer cap comes off the gearbox. It may be "stuck" or a good fit. There are 2 more bolts holding the inner to the engine.

We are not selling gearboxes, and I am not excited about any of the ones available, tho the Grube seems to be the getter of what's available.

The noisy, poor quality gearboxes are giving the 4-stroke engines a bad name it seems.

Mike

 

[adventureluck]

Yah I think I'm just gonna do what I should have in the beginning and get a golden eagle. Nowhere on the net are people saying they are bad, only good reviews, ONLY japanese and/or american parts, and they 100% get the rated gas mileage so if I get the 35cc 4 stroke I'm getting at least 180mpg but probably more like 200mpg and way quieter/reliable than my current motor. Should pay for itself in a year.

 

[adventureluck]

I really would like a gearbox solution for what I do have because gasbike.net just told me 'oh well you get what you get'

 

[MotorbikeMike]

Hi I'm sorry that you have a bummer. I use those kits to build other types, but cannot pay very much for used kit. I use that engine, with custom adapter, and 50th sprocket successfully.

If you are interested in letting it go real cheap I may be interested, you could PM me if you like.

Mike

 

[adventureluck]

I'd like a gearbox solution if possible. I mean it can't really be that hard to get 3 gears to turn with the motor and some little balls and not make a boatload of noise.

 

[glacknoid]

By the looks of the kit you bought you have everything you need to just swap out the hoot gearbox with a grubee skyhawk stage 3. Go to Complete Gear box Assembley - $119.99. and you will have what you need for 119 plus shipping. It looks like you have a throttle with a kill switch button on it in the kit you showed a link for in your first thread. This gearbox will fit your engine if it's a honda or a huasheng. If your not sure call customer service on the link and ask for jeremy and he can set you up with what you need. You just need to get the old one off, if you can get all the outside bolts off, remove the cover and then unscrew the two inside bolts that hold the gearbox to the engine and if needed check out the instructions on mounting the stage 3 skyhawk. You may need to flip the sprocket on your rear tire depending on how you mounted it for the other gearbox so it is in line with the skyhawk. Some people mount it concave side in, some out depends on the bike and possition of the final drive sprocket on the gearbox. I had to mount mine the opposite of the instructions to get a straight line from final drive sprocket to the sprocket on the rear tire.

 

[civlized]

I have one of the same kits. I had to change one of the bolts on the engine housing behind the gearbox. The head of the bolt was too big and was bending the housing causing a loud scream when riding. At idle, it did not make this noise because the gears are not moving. I would suggest checking this. If the bolt heads all look the same, this could be your problem. If this one bolt looks different, thinner head and not touching the gear box when mounted, then you may need some ear plugs.

 

[adventureluck]

on the engine housing behind the gearbox? What? pics? links?

 

[adventureluck]

I finally got the top of the gearbox off and it is complete crap inside! the left gear (the one the engine is turning directly) is not a perfect circle and part of it scrapes across the metal on the inside of the case. As well it's rusted out! Definitely going to have to get that stage 3. Although there's gotta be a quieter gearbox - belt anyone?

 

[adventureluck]

As well can anyone tell me how to get this cursed gearbox off of my engine? I cannot remove the damn thing for the life of me. I got the cover off but now I see no screws or anything at all. And the gears won't come off.

 

[civlized]

Sorry for not having pics. I am currently at work, so I can't get to any quickly. I will get you some asap. I am talking about the small bolts that hold the lower half of the engine housing together. One of the bolts is directly behind the gear box. There is only one that could be the culprit. However, if you found that one of the gears is touching the housing, that is probably your noise. The bolt head that I was referring to caused one of the gears to rub the inside of the housing on my unit. You had a gear rubbing, possibly different cause of rubbing by your description of the drive gear.

 

[adventureluck]

Yah it's ok. It's definitely the gear touching the case in the gearbox. I spun the gears with my hand and I could see and hear what was making the sound. I just need to get the dang thing off. Ordering the new gearbox asap.

 

[adventureluck]

Alright I took my gearbox off and even my engine is rusted out. gasbike.net said 'No refunds if you opened the box.' - Word for word. So screw it I'm just going to get a japanese engine - subaru robin 35cc sounds nice. Maybe with the belt kit. Thanks for all the help though I really appreciate it. I'm gonna live my dream of being able to get 150+mpg and cruise around comfortably on a bike all day!