H
HoughMade
Guest
Depends on the gearbox. 44 teeth is geared too high for the Grubee Skyhawk Stage II and III, and probably way too high for the Hoot chain drive. May work well for the Grubee 4G.
XenonDream
Member
I have the 4G and a 44-tooth sprocket, and my bike eats hills for breakfast. 
Xenon,
The gear and drive system is excelent for your two-cycle motor! I have the HS four cycle motor! With the four cycle, we find it hard to get to speed! Top speed for me with the 44 tooth gear was around 50 mph! The problem was, I needed a down hill slope to get up to speed.
I guess, all this depends on what motor and transmission you may be running on your bike!
I have the HS four-cycle motor.;
The gear and drive system is excelent for your two-cycle motor! I have the HS four cycle motor! With the four cycle, we find it hard to get to speed! Top speed for me with the 44 tooth gear was around 50 mph! The problem was, I needed a down hill slope to get up to speed.
I guess, all this depends on what motor and transmission you may be running on your bike!
I have the HS four-cycle motor.;
XenonDream
Member
Well, bubbatgs, I have the HS 4 stroke with the 4G box, and it works great for me. I weigh 210 lbs, and it'll climb 10% grade inclines at 20+ mph. Compared to the G5 2-stroke I had before, this thing is a beast. I have half a mind to put a 40 tooth sprocket on it.
I
Irish John
Guest
That guy Sean who I supplied a 4G/HS to on a Grubee cruiser last August and about which I wrote a thread,
http://www.motoredbikes.com/showthread.php?t=22945
http://www.motoredbikes.com/showthread.php?t=22440&page=6
reports that with a 44T sprocket his top speed is 48 km\hr and I reckon that's about the same as the HS on the older Grubee GBs with a 48T - maybe a tiny bit slower cos they did 51 km\hr. Mind you he also says that is the speed the roadside computers tell him he's doing (because he hasn't got a speedo on his bike) and I'd prefer to believe a good bike speedo. Sean says the HS/4G with 44T doesn't pull well on steep hills but the hill he's referring to is a really steep and long one. 4-strokes do require a bit more pedalling on hills though. I suspect that the original 4G needed a 40T sprocket and like most 4-stroke rigs you might have to sweat a bit on a very steep hill. My experience of two HS\4G kits is that the rear pulley wheel was way too large - the attached picture shows the size I reckon it should have been and simonjohnwilmer agreed with me on this.
The new 4G I notice has reduced the wheel to about exactly this size but it has also reduced the drive sprocket from 11T to a fixed 10T which will cancel out some of the benefits of the reduced pulley wheel. Consequently I think Grubee have still got it wrong and that they may need to make the pulley wheel even smaller or the chain drivesprocket larger or both. Don Grube tells me I worry too much but I reckon he still hasn't got the GB right. The new 4G has 50T rear sprocket which I reckon will be much too large just like the 56T was too large for the Mark 2 & 3 GBs. I have just started a thread showing Don Grube's 4G plans on:
http://www.motoredbikes.com/showthread.php?t=25727
and I'd love to hear what others think about it.
The 4G is quiet which is a great plus but my experience of it is it was rushed to production with zero testing and is consequently incorrectly geared as well as being ridiculously wide for comfortable riding.
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XenonDream
Member
Different stokes, I guess. I have an HS with a 4G box (5:1 reduction) and 11-tooth drive with a 44-tooth rear sprocket. I'm 210 lbs, and I have no complaints. There aren't many hills in my area more than 10% grade, and I sail over those at 20+ mph at about half throttle. It IS a wide motor, and I had to install a wide crank (that came with the kit). It takes a little getting used to. It's not a big deal to pedal, and unless I'm broken down, I won't have to. It starts from a dead stop just as well as it does when rolling a few mph. So far, I don't have anything negative to say about it. It even smells better than my old G5.
I
Irish John
Guest
Yes Xenon I noticed it started nicely from a standing stop and it is quiet which is really good but I'm not happy with short cranks for pedalling and I was judging it by the older grubee GBs which I found to be good with a 48T. Sean had problems with the increased torque pulling the 11T freewheel to bits and I think he still hs that problem. The pulley wheel is definitely too large and, when size is already a problem, that is a real downer.
All I was saying is I think it could have been so much better but I accept that you have yours running optimally and I'm sure it performs better in traffic than the older ones.
I do think that the amendments being made will be a big improvement but still won't be as good as it could be because it isn't being properly tested and trialled and that is hard to understand and smacks of incompetence.
All I was saying is I think it could have been so much better but I accept that you have yours running optimally and I'm sure it performs better in traffic than the older ones.
I do think that the amendments being made will be a big improvement but still won't be as good as it could be because it isn't being properly tested and trialled and that is hard to understand and smacks of incompetence.
jimraysr
Member
4:1 + 5:1 = 9:1?? Not
In reviewing the ratios and verbiage on Don's "Up Grade to 2010"photo, it states that belt ratio is 4:1 and the chain ration is 5:1 for a total of 9:1.
Maybe I quit school to soon and this is the new math, but I have never seen ratios added together. they should multiply.
So 4:1 X 5:1 would be a total ratio of 20:1. That is about what I have seen for most drives. Somewhere between 18 and 23:1.
Thus a Honda wound out to 7600 would give a rear wheel speed of 380 RPM and for a 26" wheel a speed of 29.4 MPH.
If it were 9:1 then it would top out at 65 MPH. )
I notice from the profile picture that the drive sprocket doesn't seem to have the large shaft overhang like the 09 model had.
I am still in the dark as to why the clone and Honda have different mounting arrangements.
Jim
In reviewing the ratios and verbiage on Don's "Up Grade to 2010"photo, it states that belt ratio is 4:1 and the chain ration is 5:1 for a total of 9:1.
Maybe I quit school to soon and this is the new math, but I have never seen ratios added together. they should multiply.
So 4:1 X 5:1 would be a total ratio of 20:1. That is about what I have seen for most drives. Somewhere between 18 and 23:1.
Thus a Honda wound out to 7600 would give a rear wheel speed of 380 RPM and for a 26" wheel a speed of 29.4 MPH.
If it were 9:1 then it would top out at 65 MPH. )
I notice from the profile picture that the drive sprocket doesn't seem to have the large shaft overhang like the 09 model had.
I am still in the dark as to why the clone and Honda have different mounting arrangements.
Jim
Hi all i got 4G with 11 tooth drive 44 tooth sprocket, getting 144 mpg 31mph top end. i run at 25 mph. state law here is 25 mph max you will get a speeding ticket if they see you going any faster. it all about gas mileage for me anyway.
I
Irish John
Guest
Is that 4G mark1 or 4G mark2? i.e. is it the one with the smaller rear pulley wheel that came after the first model?
