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Hpi RS4 2

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rs4racing13

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Just a quick question. I just purchased a OS MAX 15cv motor and wanted to know what was needed for the install on a HPI rs4 2. I've just been rebuilding the hpi15fe for the past 7-8 years and thought it would be nice to have a different motor for once.

i have the basic engine mounts from HPI. Also what flywheel and all do i need?? Any help would be great. Thanks!!

-John
 
You shouldn't need anything, the OS will drop right in to the RS4 2. You can use the flywheel, clutch bell and clutch set up from the stock engine if you want, or pick up an MIP clutch for it.
 
Okay good, i was just making sure. I tried to fit the OS MAX .12 i have but it wouldnt go in. =[ As soon as my engine comes in i'll be sure to post pics. thanks a lot!!

-john
 
Actually the crank shaft is tooo short...it wont let me put the stock flywheel on and i can't fit the one that came with the motor because the brake disk is in the way...

is there anyway someone could post pics or send me a link for the set-up...


thanks again guys.
 
Last edited:
Actually the crank shaft is tooo short...it wont let me put the stock flywheel on and i can't fit the one that came with the motor because the brake disk is in the way...

is there anyway someone could post pics or send me a link for the set-up...


thanks again guys.

Which OS are you trying to use? If you are trying to use the short shaft version intended for use on a Tmaxx or RC10GT, then it wont work, you need the regular shaft version. You got a pic of the engine showing the shaft?
 
Well i have the OS MAx .12CV, It was installed on the HPI rs4 3. If it is the short shaft, is there a way to extend the crank or get a new one that would fit?

Thanks.

-John
 
There is no reason the .12 shouldn't work on the RS4 2. If the .15 is a short crank version, you will have to buy a new crank for it to use it in any RS4. There is no way to extend it.
 
Thats what I thought. What i'll do is take a pic. Do you know what the specs are for it to fit onto the rs4 2? I found this crank on ebay for 22 shipped. and if it will work I'm going to order it. Thank you for all your help.

this is the specs for the new crank.

SPECS: Total Length: 59.6mm (2.35 )
Connecting Rod Pin Length: 4mm (.160 )
Connecting Rod Pin Diameter: 3.8mm (.151 )
Crankshaft Bearing Diameter: 9mm (.353 )
Length of Threaded Portion: 18.6mm (.734 )

Actually, i just messured the .12 i have and it is a short crank which is fine. I will keep it in my nitro3 and the 15cv is a standard crank so i will bolt that as soon as i get it. Once again, thanks for your help pal!!!!

you saved me a lot of time and headache.

-John
 
No problem at all. But how was a short crank used in a RS4 3? I have an RS4 3 and when I went to put an OS .15 CVX Hyper I had that had been in one of my maxxes in it, I had to order a new crank for it in order to use it, since it had been cut for the maxx.
 
I have no clue, just bolts right up. i just can't get it to work with the rs4 2. :\

ill take pics of it in a bit and you can see.
 
Pics of said Rs4-2 :)

Sell it on ebay, and Grab a higher revving/better motor?

Also Grab a motor off of a HPI Rush Nitro Evo. (staduim truck) (what i have) Direct drop in, and ALOT faster/better than the FE....actually anything is better then a FE. AND its ROTO start.... so much better. Id also get a Tuned pipe while your at it.
 
LOL, just going to respond with that ^^..

I would do it. I think I'm trading one of my extra Fe's for 1 T3.0.

Good deal, or i can pay 90+ everywhere else plus shipping. plus the FE isnt worth crap nowadays since ALOT of new motors have so many advances, and really puts the FE in its place.
 
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