Custom Fighters - Custom Streetfighter Motorcycle Forum banner

Which wheels do you think will be most suitable for the RC 390

  • Aprilia RS 250 MK1 - 3" F 4.5" R (Will keep stock Tire widths of 110/150)

    Votes: 2 100.0%
  • Aprilia RS 250 MK2 - 3.5" F 4.5" R (Will Upgrade to 120/160)

    Votes: 0 0.0%
  • Ducati OE 3 Spoke "Skinny" - 3.5" F 4.5" R (Will Upgrade to 120/160)

    Votes: 0 0.0%
  • Anything else? Please recommend in reply.

    Votes: 0 0.0%
1 - 11 of 11 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
Hi guys, I have a very unhealthy obsession with putting things where they don't belong :nuts: :truestory: Like putting a dual disc front end on a baby 375cc bike. I'm looking to swap out the wheels on my RC390 with something with a dual disc front end and 320mm rotors. I've narrowed my choice down to either an old set of Ducati/Brembo/Marchesini wheels, or the OE wheels off an Aprilia RS 250 MK1/2 depending on availability. Does anyone here have any experience with the KTM 390 series of bikes and know which would be a more suitable candidate for the swap? I'm on a pretty tight budget so can't afford aftermarket branded wheels such as OZ, Galespeed, Marchesini, etc... Thanks in advance :) :cfcartman:

p.s. the forks I'm using are off the RC8, which are a direct swap over to the RC390 triples. Brakes are Brembo 100mm units off an S1000RR.
p.p.s. Option 1 is probably going to be the cheapest for me to implement, as it will save me from having to buy new tires. Also, a 5.5" rear wheel would probably not fit, and would definitely be overkill... Also, 180 tires aren't cheap :p
p.p.p.s. Some research helped me find the following wheel weights.

 

·
Registered
Joined
·
9 Posts
Discussion Starter · #2 ·
Hi guys, I've pulled the trigger on a set of RS250 MK1 wheels, will update when I get then and proceed with the install. This should be some time in July.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #3 ·
Hi guys, I'm FINALLY attempting this swap now. The front wheel bearing has an OD of 25mm and my forks are meant for a 30mm axle. One staction has a 34mm hole and the other one has a 30mm hole. I need to make a custom axle and spacers to fit my config. What I'm thinking is, I'll go in for a 25mm OD tube for the axle and on either side, make threaded spacers, so the tube can be fitted in properly. Is this a stupid idea?
 

·
The friendly Ghost.
Joined
·
13,174 Posts
How are you planning on keeping the 25 mm tube in place? Are you going to thread one end and hex the other? Weld one of the threaded portions and pinch the other?

How do you plan on keeping the spacer, bearing, spacer, bearing, spacer stack in compression to keep the wheel located without side play?
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #9 ·
How are you planning on keeping the 25 mm tube in place? Are you going to thread one end and hex the other? Weld one of the threaded portions and pinch the other?

How do you plan on keeping the spacer, bearing, spacer, bearing, spacer stack in compression to keep the wheel located without side play?
Hi, thanks for your reply. My plan is to take a 25mm OD x 4mm wall thickness titanium tube and have it threaded on both ends. on one end I'll thread on a spacer of 34mm and on the other side I'll be making a spacer of 30mm with a hex pattern, which can also act as the nut. The forks have their own pinch bolts which I will be using to hold the axle in place. Custom spacers will have to be made to compensate for any gaps. I actually had the original axle and spacers etc... from the RS250 wheels, but for the life of me, I can't find them... :wtf:
 

·
Premium Member
Joined
·
2,225 Posts
I don't quite see it but I feel sure you're making it more complicated than it needs to be. Custom making large nuts and bolts requires special tools rather than a standard lathe and costs more plus not eveyone can do it.

Could you use stock wheel bolt/ nuts at either end to simplify things?

I'd look at ways to re use original parts (maybe from other bikes) perhaps with bushes to pack them out.
 

·
Premium Member
Joined
·
2,225 Posts
Having said simpler is better, the cleverest system I've worked on was a 600 srad. Looked a bit like this:

Look at this on eBay http://www.ebay.com/itm/162152511324

The wheel spacers are part of the spindle so it was very easy to reassemble. Perhaps something like that would work, and could pack out the forks too?

Sure someone on here could measure up, you may even find that suzuki part would fit.
 
1 - 11 of 11 Posts
Top