Mongoose CX24V450 with 2500 watt L-R Small Block

[Raisedeyebrows]

With 24" Rhynolite rim & Surly disk hub on front, bumped the stack height up some more and really improved the ride over bumps over the 20" wheel, feels like going from a 26" wheel to a 29er on a MTB. Now on the hunt for a beefy 24" tire for the front and I see there is plenty of room to put another Oddyessy Aiken 2.4 on the back. Also working on battery mount although the pack fits so nicely as is I'm taking my time. Bike is pretty fast, trying to putt around town at about 20-25mph without goosing the throttle and also pedaling a lot to keep it Low Pro.

Ran into another gentleman with a LR Bike down at the grocery store a few days back, beautiful 2 stage build which was a real work of art, needless to say we shot the BS for a good while comparing notes, he said he lives up some pretty steep hills too and said his bike climbs hills like crazy.

You can see the difference in height between Daughter's bike and the one I built up for myself to ride.

[LightningRods]

Looking great Kelly! Don’t trick your bike out too much. It’s starting to look as fast as it is!

[skeetab5780]

Looking great! I bet it is really fun to rip around with them both

[Raisedeyebrows]

Looking great! I bet it is really fun to rip around with them both

Yeah it’s a real blast to ride, plenty of get up and go on tap if I need to get out of the way of something. Glad Mike could get this project to fruition before the prime riding season weather hits hard, already putting some miles on it.

I can tell he’s not trying to blow his operation up into some big huge deal, just focusing on making high quality parts, nice designs and providing customers with a genuinely pleasant and satisfying custom electric bicycle experience.

[LightningRods]

Thanks Kelly. I truly appreciate the kind words.

It was always my dream to have my own speed and custom shop, not to be Walmart. I'm very grateful not to be in that game. There are some very greedy, very ruthless individuals at the money end of the business. They deserve each other.

[EbikeAus]

I think this is the best cx conversion I've seen so far!

I've started my own build here

viewtopic.php?f=28&t=95111

I'm having a hard time finding a motor. Any input is welcome

Do you guys think this would work, without the need to change the rear sprocket?

electric car brushless DC Motor 450W or 600W 48V DC motor,High power electric bicycle brushless motor

http://s.aliexpress.com/bMn67Bbe?fromSns=

Thanks

[LightningRods]

Hi EbikeAus,
That’s a cool little motor. The built in reduction would be welcome but unfortunately I think it makes the motor too wide overall to fit between the motor chainline and the pedal chainline on the Mongoose. If you give up the pedal chain it would almost certainly fit.
They rate the output shaft at 424 rpm which is a decent rear wheel rpm. For a 26” wheel anyway. I think Kelly’s bike is doing about 600 rpm at the wheel. It’s too bad that the output shaft is 11mm. I have all kinds of resources for 12 mm bore sprockets.
You may be on to something here. If it fits and the reduction box is durable this would be a nice upgrade for your ‘Goose.
Mike

[gogo]

I've got one on the way and have a stock Currie motor to use for a comparison. I'm planning on posting the comparison.

[LightningRods]

Based on their spec sheet it's just a bit wider than the Big Block motor.

[EbikeAus]

Thanks very much for your replies!
Id be interested to see your comparison gogo!

Lightningrods, thanks for your input.
I thought it looked like that motor could go close.
I really need to be able to pedal as Aussie laws are pretty tight (rediculous) on ebikes!

[EbikeAus]

Hey Raisedeyebrows,

Was just wondering if you upgraded your rear shock.

I'm 5"10 and looking at this one.

https://rover.ebay.com/rover/0/0/0?mpre ... 1297638878

Do you think 165mm will be a good choice, or would you recommend longer?

Thanks

[EbikeAus]

Based on their spec sheet it's just a bit wider than the Big Block motor.

Just saw this motor on alibaba, from your experience working with the mongoose do you think this would fit?

https://app.alibaba.com/dynamiclink?tou ... cene=buyer

[LightningRods]

They list the width of that motor at 87.5mm +/- 2mm. The small block on Kelly's bike is 78mm wide. Kelly, how much space is there between your right side motor case and the pedal chain? It's close.

[EbikeAus]

Thanks Lightningrods!

I'll wait for Kelly's response on whether the motor will fit.

Apart from the size, do you think this motor could be a good option for the mongoose?

There are a number of variants below. I think the difference is mainly the shaft.

https://app.alibaba.com/dynamiclink?tou ... cene=buyer

[LightningRods]

This motor only mounts on the output side. You’ll need to make a bracket much thicker than the two sided mount I used on Kelly’s bike. The motor rpm at 48v is listed at 4000 for this motor compared to 3200 for the small block. That’s not really a good thing since there isn’t a lot of room to have a large reduction sprocket. A higher kv suggests less torque at the same watt rating. With identical gearing this motor will feel like it’s geared higher.

[Raisedeyebrows]

They list the width of that motor at 87.5mm +/- 2mm. The small block on Kelly's bike is 78mm wide. Kelly, how much space is there between your right side motor case and the pedal chain? It's close.

It measures out at about 10mm between the bolts on the right side motor case and the pedal chain. Building up one of these bikes could be highly simplified by just purchasing a small block motor and mount from Mike, it all fit really nicely. On the left drive side the #217 kart chain clears the swingarm by enough that I put a piece of gaffers tape on the swingarm thinking there might be some rubbing but there's no marks on the tape.

The only thing I have done to the system is one chain tension adjustment after riding it about 50 miles and since then it's just been Go Go Go. The kicker is the bike pedals nicely too so when I encounter Lycra's on my travels I just slow down and pedal past them.......or cops or other possible unfriendlys.

[EbikeAus]

They list the width of that motor at 87.5mm +/- 2mm. The small block on Kelly's bike is 78mm wide. Kelly, how much space is there between your right side motor case and the pedal chain? It's close.

It measures out at about 10mm between the bolts on the right side motor case and the pedal chain. Building up one of these bikes could be highly simplified by just purchasing a small block motor and mount from Mike, it all fit really nicely. On the left drive side the #217 kart chain clears the swingarm by enough that I put a piece of gaffers tape on the swingarm thinking there might be some rubbing but there's no marks on the tape.

The only thing I have done to the system is one chain tension adjustment after riding it about 50 miles and since then it's just been Go Go Go. The kicker is the bike pedals nicely too so when I encounter Lycra's on my travels I just slow down and pedal past them.......or cops or other possible unfriendlys.

Thanks a lot for the reply!
I'm loving this little bike already just with the original motor on 36v..but definitely needs an upgrade!

I've been having a hard time trying to find avsuitable motor to use.

The small block sounds great!

I've sent Mike a PM and email on his website about buying a small block, mount and sprocket, so hopefully

[LightningRods]

EbikeAus- I’d be happy to sell you a small block, sprocket, and the basic swingarm bracket to get you started. I didn’t make a template of the holes drilled in the bottom plate that match the Mongoose swing arm. Depending on how handy you are you may be able to DIY that part. If necessary I’m sure that Kelly will let me have access to his bike to measure the spacing on the bolt holes.
I haven’t received either a PM or email from you. I’ll PM you now.
Mike

[EbikeAus]

EbikeAus- I’d be happy to sell you a small block, sprocket, and the basic swingarm bracket to get you started. I didn’t make a template of the holes drilled in the bottom plate that match the Mongoose swing arm. Depending on how handy you are you may be able to DIY that part. If necessary I’m sure that Kelly will let me have access to his bike to measure the spacing on the bolt holes.
I haven’t received either a PM or email from you. I’ll PM you now.
Mike

I'm starting to think a couple of my PMs haven't got through lately.

Thanks for the reply Mike, I'll email you tonight.

[Raisedeyebrows]

I should also mention the Em3ev 52v 16.5ah battery in the rectangle case just happens to be a darned near perfect fit for the frame, I've been lagging on getting a bracket made for it as it is perfectly fine with a couple of Scuba straps and Velcro straps holding it, Em3ev's case is really thick and just sits in there tightly and hasn't moved with the straps on. For a person modding one of these bikes that battery is a good purchase, worth spending the money. Works well with the Small Block Motor.

[EbikeAus]

Hey Kelly,
how's your mongoose going?
Could you tell me how many links your chain has please, as I'm looking to order mine soon?
Thanks

[LightningRods]

Kelly came by my shop today. The 219 chain has 132 links.

[EbikeAus]

Kelly came by my shop today. The 219 chain has 132 links.

Mike thanks.

Would be good to hear an update on your mongoose Kelly. Have you made any further mods?

[Raisedeyebrows]

No I have not done any mods to the bike lately, just riding it a lot and also pedaling a Mountain Bike on various trails a ton as well this summer.

Looks like putting a longer shock on is totally doable and should get you a bit more seat height, appears one would not cause any clearance problems either, I am going to see what I can find in the way of shocks that will work. The 219 drive chain is holding up well and the chain on the pedaling side doesn't get stressed much so it's good too. I think you'll be amazed at how the small block motor fits in there like a glove with plenty of room for adjusting the chain tension as well. With the 20" wheel in the back it really climbs hills like crazy.

I was careful to check the tension on the chains daily when breaking it in just to make sure either side didn't snug too much and booger up any bearings. I only did one chain adjustment and it's held fine, Mike thought the tension was looking good. Once you have the motor and bracket you should be able to bolt it together pretty quickly so looking forward to seeing another with a similar setup. What are you doing for battery?

[EbikeAus]

No I have not done any mods to the bike lately, just riding it a lot and also pedaling a Mountain Bike on various trails a ton as well this summer.

Looks like putting a longer shock on is totally doable and should get you a bit more seat height, appears one would not cause any clearance problems either, I am going to see what I can find in the way of shocks that will work. The 219 drive chain is holding up well and the chain on the pedaling side doesn't get stressed much so it's good too. I think you'll be amazed at how the small block motor fits in there like a glove with plenty of room for adjusting the chain tension as well. With the 20" wheel in the back it really climbs hills like crazy.

I was careful to check the tension on the chains daily when breaking it in just to make sure either side didn't snug too much and booger up any bearings. I only did one chain adjustment and it's held fine, Mike thought the tension was looking good. Once you have the motor and bracket you should be able to bolt it together pretty quickly so looking forward to seeing another with a similar setup. What are you doing for battery?

Sounds like it's working well for you. That's good! I'm looking forward to getting mine going better
We're coming into some better weather here, so should be able to give it a good run.

I was thinking a 165mm or 190mm shock with 50mm travel could work well but will most likely swap to a 24" front wheel first, as you did, then see where it sits.

I'm in the middle of building a 14s 5p Samsung 25R battery with bluetooth bms.
I have access to large quantities of near new power cells for dirt cheap, so cant really justify buying a pre- made battery.