rear or front mounted engine kits not for me

GoldenMotor.com

jimhebert

New Member
Dec 31, 2010
8
0
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louisiana
There are many reasons that keeps me from buying a rear or front mounted engine kit. I like the Robin Subaru kit but won't buy it because it's a rear mount.

1. The Center of gravity is higher for a rear or front mount engine. Thus the bike is not as stable as a bike with an in-frame engine that sits closer to the ground.

2. The weight of the engine for a rear or front mount engine is not distributed evenly on the tires thus effecting steering, maneuverability, and wear on the tires. As compared to an in-frame, that has equal weight distributed over the tires and the tires will wear more evenly and much better steering ability.

3. If you desire to add a basket or saddle bags to a front or rear mount engine there comes some more problems. Besides adding more weight (see 2. above), you increase the height of the CG (see 1. above) since the rack sits over the engine and makes instability that much worse. Furthermore, saddle bags will cover the engine and block the necessary air flow from contacting the engine, thus causing the engine to run hotter than normal and reduce engine life. This airflow to engine is blocked more so on a rear mounted engine since your body blocks the air stream. All of these problems don't present themselves with an in-frame engine.

4. It's a lot easier to drain the oil out of an in-frame engine that sits close to the ground, than a high sitting rear or front mounted engine. Unless you like having to stand and hold the container, on a rear or front mounted engine, while the oil drains.

5. I personally don't find a rear or front mounted engine appealing to look at. In my opinion it just doesn't look good. Each to his own. I like the way an in-frame mounted engine gives more of a motorcycle presentation.

I'm looking for an in-frame kit with an American or Japanese engine, around 35cc more or less, that has a max 1.5 HP according to Louisiana law, to be classed as a motorbike. Any comments or suggestions will certainly be appreciated.
 

scottmanesis

New Member
Dec 30, 2010
107
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Austin, TX
Can't help you with the Jap or American requirements. However, if you take the stickers off even a 66cc China kit, who is going to take apart your cylinder on the side of the road and measure the displacement or put it on a dyno to check the HP? In other words it's only as big and as powerful as you claim it is :)

Of course you don't want to be blasting down the road at 35mph when you get pulled over but if you can restrain yourself from acting like a butthead around the po po, I doubt any of the above mentioned things will ever be an issue especially if there are not many motorized bikes in your area, you will most likely buzz by totally unnoticed.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
I have to wonder if your opinions/assumptions are based on experience. I've had the opportunity to ride a number of rear rack mount bikes, both with the engine centered over the rear wheel and mounted side saddle, off to the left. I'm a lightweight, so if the weight or balance were factors I would have surely felt it. I've never experienced any instability or balance problems with either application.

That being said I will admit that, like you, I prefer the looks of an in-frame mounted engine as well as the ease of mounting/dismounting the bike. Rear rack mounts require that you either step very high, swinging your leg up and over the engine, or step across the top tube. A girl's bike (step through frame) would lend itself better to the rear mount, me thinks.

As for a front mount; I've never owned or ridden one so I will withhold any opinions on them.
Tom
 

jimhebert

New Member
Dec 31, 2010
8
0
0
louisiana
Hi
No, I haven't ever ridden a motor bike. I'm only speaking from the physics side of the equation. Although there may not be any noticeable riding effects with a rear or front mount, the weight of the engine is still not distributed evenly. I guess I may be too much of a perfectionist, but when I see this type engineering design, it just doesn't set right in my mind. Thanks for bringing up the other point about having to lift your leg real high. I hadn't thought of that one. Any suggestions where I could find an in-frame kit with a 4 stroke, 35cc more or less, 1.5HP max, American or Japanese made engine? Thanks.
 

matthurd

New Member
Dec 13, 2010
817
2
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manchester NH
following the rules is going to cost you a lot more upfront then a little white lie will, also it makes it much harder for your inframe preference to be viable. with that being said heres some quality engines within your size limit, but they're wheel mounted, not inframe. also they don't list HPs but at least its the within your displacement limit.

i haven't seen any in frame motors below 48ccs although i'm new to this as well.

Golden Eagle Bike Engines, Geared Belt Drive Bicycle Engines / Motors for Mountain Bikes & More
 

jimhebert

New Member
Dec 31, 2010
8
0
0
louisiana
Ok, I'm pretty set on in-frame kit. I'll try calling the places you suggest and maybe they'll have a lead. Thank You for the info.
 

scottmanesis

New Member
Dec 30, 2010
107
0
0
Austin, TX
I still say strap on the 66cc and keep an eye on your speedo when the po po are pokin around. Nobody is going to break out measuring instruments or a dyno on the side of the road.

Disclaimer: I do not endorse or promote illegal activities and all posts are for entertainment purposes only. In other words if you do happen to get busted (unlikely unless you act out like a jerk on your bike) you cannot say Scott said it is ok.
 

5-7HEAVEN

Well-Known Member
Aug 2, 2008
2,661
240
63
Seems like center-frame build is for you. Japanese engine would be Honda GX50, which I believe has that center-frame kit.

If wanting lower-hp engine, then you're on your own in fabbing such a build.
 

msrfan

Well-Known Member
Sep 17, 2010
1,808
120
63
Southern California
Hi
No, I haven't ever ridden a motor bike. I'm only speaking from the physics side of the equation. Although there may not be any noticeable riding effects with a rear or front mount, the weight of the engine is still not distributed evenly. I guess I may be too much of a perfectionist, but when I see this type engineering design, it just doesn't set right in my mind. Thanks for bringing up the other point about having to lift your leg real high. I hadn't thought of that one. Any suggestions where I could find an in-frame kit with a 4 stroke, 35cc more or less, 1.5HP max, American or Japanese made engine? Thanks.
The old Whizzer adds say "ride one and you'll buy one". I suggest finding motorbikers in your area and begging a test ride. Maybe going to a meet and checking all the different assemblies.
 

virginian

New Member
Dec 19, 2009
117
0
0
McLean VA
I have to wonder if your opinions/assumptions are based on experience. I've had the opportunity to ride a number of rear rack mount bikes, both with the engine centered over the rear wheel and mounted side saddle, off to the left. I'm a lightweight, so if the weight or balance were factors I would have surely felt it. I've never experienced any instability or balance problems with either application.
I completely agree. I have a rear mount GEBE setup. Before I completed my build I had some worries about balance and high center of gravity, but after riding my new motor bike, I found they are not an issue at all. The bike rides beautifully with no feeling of being unbalanced or top-heavy.
 

jimhebert

New Member
Dec 31, 2010
8
0
0
louisiana
I have never seen a motorbike in my area. I don't think there any clubs around my area. I saw the whizzer on Youtube and I like it a lot. It's got the in-frame which is what I prefer. The Titan engine that thatsdax has one that is in-frame. I will make a few phone calls tomorrow and find out about the make. I don't want Chinese. I'll find one soon. thanks
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
24
38
Ridin' inSane Diego, CA.
Just don't want poor quality.
Well I ride and own 4-stroke in-frame cruisers but here is a rear-rack exception of high quality that you don't have to throw yer leg over.....you just step right through to be seated. It's a Japanese engine of 1.2 hp x 3.5 that's made by Kawasaki. Fast, smooth and quiet......and it seats two!



Have you considered the 1.6 hp Honda GX 35 4-stroke? We won't tell anyone that it's over 1.2 hp.....promise! http://www.smallenginewarehouse.com/product.asp?PN=GX35&desc=Honda Engine 1.6hp GX35 OHC Mini 4 Stroke Clutch-Drive (Horizontal or Vertical Mount) 7000 RPM
 
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David D.

New Member
Sep 12, 2010
146
0
0
California
Quality reasons? i worked for a number of years at a very large manufacturing company in the United States of America.... based in Amarillo Texas..... had good ole boy mentality.... and decades of engineering experience at our disposal... had been having quality control problems with our castings and machining.... we built geardrives for a number of applications...so the president and head engineer made a trip to China to check things out....needless to say they were completely dumbfounded by what they saw..... state of the art machining centers... incredible throughput capabilities and cost about half of our U.S. suppliers .... we made the change and never looked back... ended our quaility and our delivery problems for good..... until workers here in the U.S.A. realize they have to actually work.... it will not change.
 

jimhebert

New Member
Dec 31, 2010
8
0
0
louisiana
I'm sure there are exceptions for every case, but overall, not only I but many people will say the same bad things because they have a bad experience with a Chinese product. I can think of several recent examples right this moment. I live in Costa Rica and my friend bought an extension cord supposedly made to carry a large current and the cord was very large in diameter and rated for several amps. He connected the cord and in a few minutes it was on fire. Fortunately he was around to extinguish it and disconnect the cord. He then cut the cord to examine the conductor and it was a very thin conductor which was not capable of carrying a heavy current.

I personally and also have had people tell me how they have bought Chinese shoes only to see the soles come off in a few weeks.

Last year, in Panama, about 100 people died from toothpaste which had anti-freeze, a highly toxic poison, in it. The list of products that the FDA has banned from China is volumes long.

I could list other examples, lead paint in toys, etc. but I don't want to take any chances with any Chinese product of any type.
 

scottmanesis

New Member
Dec 30, 2010
107
0
0
Austin, TX
In 2008 I purchased a Keystone toy hauler camper. The first trip down the road the not filed sharp edges of the aluminum frame tore the rubber roof about 4 feet long down the side of it. Then when I got it parked and hit the button to put out the bedroom slide, the bottom strip of the bed ripped the carpet and popped off. At the same time the corner molding on the outside simply fell on the ground because it was not attached.

3 years ago, over 200 Dometic refrigerators just burst into flames due to faulty propane hose wiring in these same campers.

I know this is not a camper forum, however my point is this model camper is $50k+ and is made in America! If you look for the bad you will find the bad. When things are mass produced you are bound to get some bad apples.

Toyota cars are made in Japan.....how many of those have been recalled recently due to situations that could and have caused fatalities.

You are not necc going to get a better product because it was made in Japan (who by the way outsources most of their work to China and Korea) or made in the USA.
 

fixalot

New Member
Mar 20, 2011
1
0
0
miami
In case you still looking for a solution you may want to give a call to Jim tell Raul from miami toll you that he may can help you here is his number..flg.
(801)830-8465
Explain him your need and good luck.