CDI
The aftermarket CDI will increase your rev limit and increase timing advance. The aftermarket CDI makes all years faster but how much faster depends on if you are hitting the rev limiter.
Starting in 2006 Honda increased the rev limit on the Ruckus and Metropolitans from 8000 to 9000rpm. The limiter starts to effect speed about 100rpm or so before the max. Installing a CDI boost box on a 2005 and older will give you that boost of the newer model and more. Of course your 2006 and newer scoot will be faster too (^_^)
The CDI is also needed for the install of a big carb kit, cam, exhaust or intake mods. You can get away with out in some cases but we are trying to make your scooter faster not get away with things. The CDI is proven to work at this point and if you want to go faster it should be number two on your list.
INTAKE
The best bang for the buck by far is the drop in air filter. A five dollar bill buys you at least 1mph, better hill climbing and acceration. Your scoot can stand a little leaner fuel mixture and the drop in air filter gives it to you. No jetting is required for this mod.
You can drill holes in your stock airbox or remove it completely to let more air in. The stock carb is a bit small so doing this will only help with acceration if done right. Don't get into this part unless you are willing to do carb jetting changes. Jetting is a trail and error job that takes hours to do correctly. It is worth it if you want to spend to time required.
Those is high altitude and heavy riders can also benefit from airbox mods and jetting changes. In these cases you can gain more top speed just by making sure your engine is tuned for your use.
EVERYTHING ELSE - STAGES
People love stages so I caved in made some up
1. Speed Variator Kit - couple MPH usually about 3mph but potentially much more.
Drop In Airfilter - 1 MPH and better all around performance.
a. CDI Boost Box - couple MPH usually about 3mph but potentially much more.
2.
Big Carb Kit - 4+MPH increase in top speed - slight driveability issue (worth it)
Exhaust System - couple MPH - more noise, a must for Stage 3
3.
HO Cam - couple MPH - makes all the other mods work better
High Compression - Decking the case or milling the head will give the engine punch
4.
Big Bore - Battlescooter has the only BIG BORE for the Ruckus/Metropolitan engine. The high compression Big Bore is as big as you can go. The case kit will put you over 50MPH and make your scooter the baddest mother in the valley. Available on line soon.
5.
Big valves or swap the motor?
06' and newer Ruckus/Met, faster?--
Well, mine wasn't but some are. The changes that made the most difference are lighter roller weights, increased rev limit, better intake tube design, better jet needle design. I do know that Honda has been changing the parts but not the numbers. There are part changes for the better in the motor and keeping the hot rodders oath I'm not telling (^_^)
I looked at all the part numbers for the early models and 06'. I even looked at drive, bearings, washers. Any parts that had to do with friction, elec. or engine. This is what I found:
1. Of course we know the ECM and harness are different because the 06' has an ECM controlled PCV system. The new system uses the chain tensioner as the case vent.
a. The new tensioner/vent part# is 14520-GEZ-611. You can use this part without the complicated 06' PCV system but you do need a couple other widgets.
part # 91301-027-000 part # 91306-105-690 part # 14525-GEZ-610 part # 90461-357-000 part # 90004-GHB-630
b. Install the 06' tensioner ass. and route a breather hose to the existing valve cover vent line with a T-fitting.
2. Muffler- new part # 18300-GET-610
The next one may be because of the new needle or different design.
3. Carb.NVK00H A- new part # 16100-GEZ-612 4.Needle- new part # 16151-GEZ-612
The airbox has changed to allow for the integrated PAR valve. The snorkel/intake side has the
same
part# but
the sub assembly has changed as well as the intake tube.
5. Case sub-ass. air cleaner- new part # 17225-GEZ-610
6. Tube, air cleaner connecting- new part # 17255-GEZ-610
I'll keep adding to this article as I remember factors I left out.
Feel free to contact us with things we should add.
Your help is always appreciated to keep things running and pay for dumb ideas.