Honda CX 500 Forum banner

Which Option for the build?

  • Option 1 - Turbo

  • Option 2 - 500 overhaul

  • Option 2 - 650 conversion

Results are only viewable after voting.
1 - 1 of 1 Posts

263 Posts
Discussion Starter #1
So, A while back over the course of a couple of years I rebuilt a ratty old CX500

In to this

I dubbed it the CX500GT. The GT came from the front USD fork version which came off of a Hyosung GT250.

Unfortunately about 6 months after I finished the project the bike was vandalised. They did considerable amount of damage to the wiring harness, they stole one of the Murray's Carbs I had installed (Just 1 for some reason). They ripped off whatever they could and broke what they couldn't. This all happened while it was parked in my driveway one day.

I lost a lot of interest in it after that and I just didn't have the morale or the motivation to fix it again.

But things have changed and it's now time to revisit.

Version 1.0 was an overhaul of the aesthetics of the bike and how it handled, a modernisation of the electric system to include keyless ignition and and LED's all over.

This time, I want to focus on power and I'm in the planning stage.

I have a few options i'm considering and here are the outlines

Option 1:
Turbo, convert to a single Mikuni TM40 flat slide carb draw through setup most likely utilising a GT20/18 or similarly sized turbo. Convert to electric water pump and move to an Ignitech ignition system.
Notes: Lots of custom fab work, likely to need a lot of fiddling to get a nice rideable bike with the turbo

Option 2:
Total rebuild of the 500, new pistons and cams (Ala JimL), Murrays VM 34's, Ignitech. Focus on high compression and ignition timing running 98 Octane or possible E85. Electric pump conversion.
Notes: Should be a nice clean look, no messy plumbing like the turbo. Will be quite expensive and require a bit of work on my end to rebuild, lots of parts ordered from overseas.

Option 3:
650 Motor conversion. Run a 650 motor with 500 cam and heads, which should up compression and be a little more aggressive cam profile. Electric water pump conversion, ignitech ignition. Once again an aim on higher compression ratio with high quality 98/E85 fuel to support ignition timing and higher compression.
Notes: 650 motors are hard to come by in my country, unsure if the VM34's are compatible with the 650 motor. This is likely the cheapest option with the best outcomes.

I have about $3-5K to spend, the goal is to get around 70HP to put the bike in the performance range of a modern 650 bike like the Kawasaki Ninja 650r or the Suzuki SV650.

As it goes with more power you usually need to upgrade other aspects of the bike as well so to ease concerns I've already done the following to the bike:
Bigger dual disk front brakes with braided lines
17" wheels with soft radial tyres front and rear
45mm(I think) front USD forks and new shocks on the rear

I'm quite confident with the above that the bike/chassis can support an increase in power and still be able to come to safe stop.

I'd like to get some feedback on people regarding these options and possible issues.

Stay posted guys, this is gonna be an adventure.
1 - 1 of 1 Posts