Does a Steel Sleeve Cylinder Matter At All?

[scottmanesis]

I am getting ready to order my first engine kit soon. I have read almost everything that I can concerning these kits on this forum and so far the consensus is that they are all pretty much the same engines more or less.

My question comes from reading the engine guide on Bikeberry. They Say

"The biggest stand alone feature that differentiates this kit over any other on the market is that the Grubee Starfire engines come with a steel sleeve cylinder. This feature alone will double the expected usable life of the engine kit. "

I will be using this bike as a daily commuter and am really curious if this matters at all and if the above statement has any validity concerning the life span of the engine. Granted they are only cheap motors but 100+ bucks is 100+ bucks. Has anyone owned or ran the steel sleeve and does it make a difference and are there other engines with other names that have the above mentioned steel sleeve cylinder??

Thanks for posting your thoughts on this particular subject. I don't want to turn it into another is this engine better than that engine as it has been posted numerous times but I do not see anything in regards to this particular oddity on the Starfires.

 

[MotorBicycleRacing]

Grubee Starfire GT 4 66 cc are my favorite motor.........They DO NOT
have a steel liner.
They have the usual chrome lined aluminum barrel.
I have never seen a 66 cc aka 80 cc motor that has a steel
liner.
Bikeberry is simply wrong which is not surprising as they really
don't know much about these motors and kits, they just sell them.

Some of the 49 cc motors have a steel liner and I had problems
with them like the steel liner was pressed in twisted so that it blocked the
ports by about 3/16" on one side. I also had a steel liner that was bored
so crooked that it was obvious without even measuring.

I am getting ready to order my first engine kit soon. I have read almost everything that I can concerning these kits on this forum and so far the consensus is that they are all pretty much the same engines more or less.

My question comes from reading the engine guide on Bikeberry. They Say

"The biggest stand alone feature that differentiates this kit over any other on the market is that the Grubee Starfire engines come with a steel sleeve cylinder. This feature alone will double the expected usable life of the engine kit. "

I will be using this bike as a daily commuter and am really curious if this matters at all and if the above statement has any validity concerning the life span of the engine. Granted they are only cheap motors but 100+ bucks is 100+ bucks. Has anyone owned or ran the steel sleeve and does it make a difference and are there other engines with other names that have the above mentioned steel sleeve cylinder??

Thanks for posting your thoughts on this particular subject. I don't want to turn it into another is this engine better than that engine as it has been posted numerous times but I do not see anything in regards to this particular oddity on the Starfires.

 

[matthurd]

new cylinders probably aren't going to cost much and most people from my understanding do not need to replace them very often no matter what type they use.

i don't think it's a huge selling point, just there to make it look better in advertising, if it was so important don't you think other manufacturers would have followed suit n made something similar to stay competitive?

gas bike.net sells new cylinders for $10 a pop, $10 every 2-3 years of use doesn't seem like a big deal to me.

also whats your budget? iv'e been talking with duane from thatsdax.com about the 2 stroke GT50R kit ($299+shipping), and he has me pretty excited about it, seems to think it's even better then his 4 stroke kits he sells, while offering significantly more speed + power, his 4 stroke set up at the same price he said tops out at 32 mph, the GT50R goes between 36-40 from what hes seen on testing. just an option. if you're interested in the gt50r heres the thread about it http://motorbicycling.com/f23/new-dax-gt50r-racing-motor-22837-15.html#post246844

good luck on what ever you pick.

 

[scottmanesis]

Thanks for the input. I thought it was odd that nobody on this forum seemed to mention anything about this steel cylinder sleeve. Goes to show ya, believe nothing that you read from advertisers!

I looked a bit at that GT50 motor. I think it would stand out alot more and I am trying to be discreet as in, I don't want the po po messing with me because of the ever so obvious engine. The china girls look to be a bit more discreet, otherwise I would just strap a freakin briggs and strat to the back wheel. I don't know, I just like the looks of the china motor for some reason.

Also the pull start on the motor changes things a bit concerning the "grey area" on the law here in Texas. The China girl cannot be started without peddle assist, so the bike remains a motor assisted bicycle as it can not run without being peddled technically.

If budget were no concern I would just spring for one of those italian motors

As it is I see myself spending about 800 to get my bike near where I want even with the china motor, if it's going to go over a grand I might as well buy a small motorcycle.

My wife used to have a Yamaha Zuma 50cc, i am pretty sure that had a Moroni in it. It would carry my fat butt around at about 40mph no problem with very little modification ( a dremel on the throttle stop).

Now I am leaning toward the Skyhawk Rat Racer with this new info. Thanks.

 

[MotorBicycleRacing]

Bikeberry also claims the Grubee Starfire has 5 - 6 HP (horse power)

The Grubee factory plate on the sprocket cover says 2.85 HP so are they
lying or are they just incompetent fools?
i doubt if they have ever taken one apart or had the head off.
they probably don't have any parts for starfires

Anyway I really like the Grubee Starfire without its steel liner so I would
recommend buying one.
there are still a few companies selling them.

 

[Goat Herder]

Bikeberry also claims the Grubee Starfire has 5 - 6 HP (horse power)

The Grubee factory plate on the sprocket cover says 2.85 HP so are they
lying or are they just incompetent fools?
i doubt if they have ever taken one apart or had the head off.
they probably don't have any parts for starfires

Anyway I really like the Grubee Starfire without its steel liner so I would
recommend buying one.
there are still a few companies selling them.

Now I have heard the steel liner roomer before. Do you have any documentation on this? I got the impression they was all A nickle type plated.

 

[matthurd]

Bikeberry also claims the Grubee Starfire has 5 - 6 HP (horse power)

The Grubee factory plate on the sprocket cover says 2.85 HP so are they
lying or are they just incompetent fools?
i doubt if they have ever taken one apart or had the head off.
they probably don't have any parts for starfires

Anyway I really like the Grubee Starfire without its steel liner so I would
recommend buying one.
there are still a few companies selling them.

2.75 hp on sky hawk GT5s http://motorbicycling.com/f14/newbie-ready-go-26332.html think the attachment is on page 2 of that thread.


as for a morini, this full kit is about half the price of just the morini motor from what i can tell.

discretion? this things a lot quieter then the china girl kits based on the videos of it i saw, and i think it could be written off as a rear rack from a distance. doesn't have an exhaust pipe hanging off of it, and no chain sticking out like a sore thumb.

the super rat does look like a nice option though. considered picking one up on my next project but i'm definitely leaning towards the GT50R kit now, or maybe a good 4 stroke with a bit less power and speed but more convenient since i wont need to run a mixed fuel and 4 strokes in general tend to have a higher life expectancy although thats debatable with these things.

anyways good luck on your build

 

[scottmanesis]

My 2 concerns with the Super Rat now are

1) How much bigger is it front to rear? (it would stink to buy a motor that does not fit most frames)
2) It doesn't look like you can upgrade the plug wire.

Also the price on gasbike.net went up 15 dollars while I was looking at it tonight...lol. By the time I make up my mind it will be $500. HAHA

I might just go back to my original plan of the Starfire or the Skyhawk (I don't see the difference between the two now that I have learned there is no steel cylinder sleeve). It will just come down to which one I can get a better deal on. Would like to hear from others who try out the Rat but I must admit I am torn. I am just worried about the fitment. An awesome engine still stinks if you can't get it in the bike. The bike I will be using is a Greenline BC106 which SHOULD work fine with the non RAT China girls but I am already slightly concerned as I don't see too many people on this forum building those and wondering why.

@Matthurd I hear ya, I just am not wanting to do a friction drive/rear motor build right now. If it works out great for folks I might pick one up and stick it on my mountain bike. For my first build I want to do a cruiser that looks like an early 1900's motorcycle of sorts and let those who are not in the know scratch their heads.

 

[Rockenstein]

The only real advantage to using a sleeved cylinder in any engine is serviceability. I mean with some engines if you happen to pop a piston or a ring and ruin a bore it's much easier, and cheaper, to press in a new sleeve as opposed to re-boring and re-plating. This is especially true on large multi cylinder engines. There are some engines that can be re-sleeved without the need to remove the engine from the vehicle, that obviously saves labor and downtime costs. For our little 2 strokes tho using a sleeved cylinder is pretty much pointless.

 

[Goat Herder]

The only real advantage to using a sleeved cylinder in any engine is serviceability. I mean with some engines if you happen to pop a piston or a ring and ruin a bore it's much easier, and cheaper, to press in a new sleeve as opposed to re-boring and re-plating. This is especially true on large multi cylinder engines. There are some engines that can be re-sleeved without the need to remove the engine from the vehicle, that obviously saves labor and downtime costs. For our little 2 strokes tho using a sleeved cylinder is pretty much pointless.

I have the impression none of the Chinas came sleeved?

 

[Rockenstein]

I have the impression none of the Chinas came sleeved?

I recall seeing pics of some that were sleeved at one of the sellers sites, don't remember which one it was tho. I remember thinking to myself when I seen them that rather than needlessly sleeve these things why not invest that time, effort and cost into making some of the other more important things better...ie: crank shaft run out tolerances, port timings, bigger cooling fins, better combustion chambers, doweled crankcase halves etc.

 

[MotorBicycleRacing]

I have the impression none of the Chinas came sleeved?

none of the 66 cc have steel sleeves

Grubee 48 cc GEN II came with a steel sleeve
Made by Nantong JiaLi
It had larger crank bearings, carb mounted on the cylinder head
with no intake manifold
It also had a larger front engine mount
the sprocket cover was not interchangeable with a 66 cc motor
It used a pocket bike carb, intake port was rectangular.

I still have one cylinder with a crooked steel liner and
the cylinder head which had a really small combustion chamber,
large squish band and a slant plug

BGF sells? / sold the same steel lined 49 cc motor

 

[scottmanesis]

Click the banner above these threads for the bikeberry engine guide. They could be liable for false advertising? I also noticed the engine kit descriptions have some outlandish horsepower claims as well. At least the prices are decent in fact the prices are better than many of the vendors on this site.

Example:

Grubee Skyhawk Angle Fire
Bikeberry=179.00
Spookytooth= 225.00

Same kit, crazy.

 

[matthurd]

Click the banner above these threads for the bikeberry engine guide. They could be liable for false advertising? I also noticed the engine kit descriptions have some outlandish horsepower claims as well. At least the prices are decent in fact the prices are better than many of the vendors on this site.

Example:

Grubee Skyhawk Angle Fire
Bikeberry=179.00
Spookytooth= 225.00

Same kit, crazy.

false advertising is a very real possibility but who would want to pursue it? only someone who hasn't done their research would believe it, and if you dont do basic research chances are your build isn't going to go so well anyways.

as for pricing, wholesale price to different dealers is not always the sameso they may actually be paying more for their kits, and then passing the cost on to their customers.

 

[matthurd]

My 2 concerns with the Super Rat now are

1) How much bigger is it front to rear? (it would stink to buy a motor that does not fit most frames)
2) It doesn't look like you can upgrade the plug wire.

Also the price on gasbike.net went up 15 dollars while I was looking at it tonight...lol. By the time I make up my mind it will be $500. HAHA

I might just go back to my original plan of the Starfire or the Skyhawk (I don't see the difference between the two now that I have learned there is no steel cylinder sleeve). It will just come down to which one I can get a better deal on. Would like to hear from others who try out the Rat but I must admit I am torn. I am just worried about the fitment. An awesome engine still stinks if you can't get it in the bike. The bike I will be using is a Greenline BC106 which SHOULD work fine with the non RAT China girls but I am already slightly concerned as I don't see too many people on this forum building those and wondering why.

@Matthurd I hear ya, I just am not wanting to do a friction drive/rear motor build right now. If it works out great for folks I might pick one up and stick it on my mountain bike. For my first build I want to do a cruiser that looks like an early 1900's motorcycle of sorts and let those who are not in the know scratch their heads.

the rats are fairly new, and also cost more money but people did seem interested in them. and i agree i do like the look of inframe motors a bit better, but that GT50R has so much more power im really tempted to pick one up, although it probably will burn through tires pretty fast since it has two high speed contact points (the street+ the roller), as opposed to chain drive systems only having one.

theirs also concerns of people not being able to use current bolt on parts like the expansion chambers, which mite be part of why the super rat may not be getting picked up as much.

 

[Goat Herder]

I like the positive pear pressure that keeps this place honest. Roust them make them change it . Or it only gets silly from here on. That might be off to say but still just saying..

Eventually legislators will take off with the claims or something too?

 

[sbech]

In short, steel (or cast iron) inner tube in cylinder does matter in repair. It can be repaired without buying new cylinder - just bore old one (if you have appropriate equipment, of course) and use a bigger piston. It has no scene, if you dont have spare pistons, bigger, and if new "normal" cylinders are cheap.

And - steel cylinder is not so easy to devastate. If you run it with bad fuel, bad oil, and overheat it, so piston started to stuck inside - you just stop, wait until it cools down, and move again. Steel cylinder will not be damaged.

 

[sbech]

Even damages like this:

can be repaired in case of thick steel cylinder, that is the matter.

Cylinder repair:

 

[phoobarnvaz]

As it is I see myself spending about 800 to get my bike near where I want even with the china motor, if it's going to go over a grand I might as well buy a small motorcycle.

Until I got mine up & running last summer...even with all the problems with the electrical system...I never got the looks/questions all the years I rode a 180 to an 850 cc motorcycle. Probably the closest thing I would approximate riding an MB would be a stripper/porn star coming to your small town. Not everyone is excited...but those who are are almost fanatical.

The reason is that people are looking for something fun and cheap to ride around on. Not having to buy tags/title/insurance/very little gas/oil...it's almost the perfect ride for someone who wants to turn heads without a big cash outlay past the bike/engine.

 

[flybytaco]

my first engine was a steel sleeved gen 2 starfire and i was so mad i wasted my money!!!

 

[flybytaco]

Even damages like this:

can be repaired in case of thick steel cylinder, that is the matter.

Cylinder repair:

a steel sleeve is good for repair(ONLY) when you can actually get an oversized piston lol