SO here is what my problem is. I have all HPI RS4's. All of them have the .15 nitro star motors on them. I recently purchased a new O.S. 18 CVRX (S) motor, and I want to put this on one of my RS4's. The problem is that I cannot find a flywheel that will go on the shaft, that will allow me to use my clutch bell. I need to know how to match up the O.S. motor to my RS4 gears. So if anyone knows what I need, Or if I am doing something stupid, and need to go with something different, then let me know.
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Need help finding a fly wheel
- Thread starter viper711
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I had a HPI NitroMT which I believe is one of the older RS4's. I installed the stock flywheel/clutch/clutchbell on my 18cv-r(x) without much of an issue other than a pull start clearance problem.
What doesn't appear to fit for you? Did you get the OS with the threaded standard shaft or something else? I believe the HPI 15's had a standard threaded shaft, so the hardware off them should work with other standard shaft engines.
Oh... wait, just noticed you have the (s) engine... it has a short shaft. I'm not sure what to tell you now. Other than return it for a standard shaft. I believe the stock setup required a standard shaft engine like this:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGGP7&P=ML
What doesn't appear to fit for you? Did you get the OS with the threaded standard shaft or something else? I believe the HPI 15's had a standard threaded shaft, so the hardware off them should work with other standard shaft engines.
Oh... wait, just noticed you have the (s) engine... it has a short shaft. I'm not sure what to tell you now. Other than return it for a standard shaft. I believe the stock setup required a standard shaft engine like this:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGGP7&P=ML
Last edited:
beason
Bash, Fix, Repeat..
can you take pics of the two? I'm with olds, I'm confused as to what wont fit. the flywheel should go on fine. but if olds is right then your shaft will be to short.
you can exchange the mill, or just get a pilot shaft for it. you will have to measure carefully so you know how long of one you will need.
http://www3.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=pilot+shaft&search=Go
you can exchange the mill, or just get a pilot shaft for it. you will have to measure carefully so you know how long of one you will need.
http://www3.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=pilot+shaft&search=Go
Beason, that would work, but the stock flywheel is super thick. I don't think there's enough shaft on a short threaded shaft engine to use it. The chassis/engine mount also won't let you slide the engine forward even if you could find a flywheel that worked.
I'm fairly certain you need to get either a new engine or a new crankshaft.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGMM2&P=ML
This is similar to the flywheel I had on mine: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM759&P=7
Except mine wasn't lightened. Where the collet goes is really thick front to back though which requires a longer threaded portion on the crank.
I'm fairly certain you need to get either a new engine or a new crankshaft.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGMM2&P=ML
This is similar to the flywheel I had on mine: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM759&P=7
Except mine wasn't lightened. Where the collet goes is really thick front to back though which requires a longer threaded portion on the crank.
- Thread starter
- #5
I have been worried about the short shaft and I think that will be a problem. So I will swap it for a longer shaft. The other problem is the shaft diameter. The OS motor has a larger shaft than my nitro star does. I have the nut adapter that will screw onto the OS motor and my clutch bell will go on to that piece good. I just need to find a fly wheel that has a large enough hole to slide on the shaft. Have any of you ever drilled one out. I know it would have to be perfect. I am open for all suggestions.
Here are my flywheel and clutch bell if you need to see them.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM724&P=7
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM759&P=7
Here are my flywheel and clutch bell if you need to see them.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM724&P=7
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM759&P=7
That flywheel should fit the standard shaft OS. My stock flywheel did on my nmt without issue onto the same engine.
Is your collet stuck in your flywheel maybe? Making it appear smaller and not fit?
This is the one I had I believe mated up with a OS 18 cv-r(x): http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM718&P=7
Is your collet stuck in your flywheel maybe? Making it appear smaller and not fit?
This is the one I had I believe mated up with a OS 18 cv-r(x): http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXM718&P=7
- Thread starter
- #7
The collet is out of the flywheel, and the odd part is that the flywheel will go over the threads on the shaft but stops about a half inch from the crank case, because the shaft is larger behind the threads. The threads do not come out past the flywheel to screw my clutch nut adapter on it. So all of my problems might be because the OS is a short shaft. I am going to go to the hobby shop this weekend and find out if the longer shaft will allow me to put all of my gear on it. I will keep you all posted incase anyone else runs into the same problem. Thanks for all the help! Lets hope I can get this thing going.
- Thread starter
- #8
I got my car going today, so I was going to let you all know the deal, incase someone runs into the same problem. The .18 cv-rx (s) has a short shaft that has a larger diameter shaft. My .15 nitro star fly wheel would not fit on the shaft and it was not long enough to reach my gears.
Today I exchanged the motor for a .18 cv-rx the only difference of course is the (s), which stands for standard shaft. The new one without the (S) has the longer shaft that would reach my gears. Now came the suprise. Even though both the motors are .18 OS cv-rx's the motor with the longer shaft also has a smaller diameter shaft. I took my flywheel off my RS4 and it slides right on to the new motor with the longer shaft. Don't know why the short one is larger than the long shaft, but I don't care, because it works now. So let anyone know that is thinking about doing this swap, that they need to get the plain cv-rx not the cv-rx (s). I mounted it on my car tonight, so now I just have to go though the pain of waiting to see what it will do until I get it broken in. Thanks for all of your input!
Today I exchanged the motor for a .18 cv-rx the only difference of course is the (s), which stands for standard shaft. The new one without the (S) has the longer shaft that would reach my gears. Now came the suprise. Even though both the motors are .18 OS cv-rx's the motor with the longer shaft also has a smaller diameter shaft. I took my flywheel off my RS4 and it slides right on to the new motor with the longer shaft. Don't know why the short one is larger than the long shaft, but I don't care, because it works now. So let anyone know that is thinking about doing this swap, that they need to get the plain cv-rx not the cv-rx (s). I mounted it on my car tonight, so now I just have to go though the pain of waiting to see what it will do until I get it broken in. Thanks for all of your input!
