Design Cycles Street Legal CRF450X Frankenstein bike

Street Legal Honda CRF450X

Street Legal Honda CRF450X

Design Cycles out of Florida has designed a kit to make a street legal CRF450X CB350F Frankenstein bike. It’s quite a unique kit compared to other Honda CRF450X Street Legal Kit and has a CAFE racer vibe to it. The kit requires a 2002-2008 Honda CRF450R or 2005-2010 Honda CRF450X as the donor bike. The frame itself is from a CB350F or CB400F motorcycle. They are also working on another kit shooting for a dry weight of 200 pounds. The kit is available to purchase on eBay or you can call them at (850) 656-0014. I’ve posted the photos from the listing and their requirements below. If you end up building this bike send us pictures! They also have some videos you may want to check out on YouTube.

This is the DCH450S Frame Mount kit that will accept

a 2002 – 2008 Honda CRF450R or 2005 – 2009 Honda

CRF450X as the donor.

Youtube video of Version 1.0 (Maroon color) is shown here. Second Youtube video will be in dry conditions in a wide open space, so we can show you more.

Or this Video

Black bike uses the kit being sold. The black bike’s wheelbase is ~2 inches shorter than the maroon colored bike. If you want the long wheelbase electric start only kit, please email us.

FYI: If you have a CRF450R or X dirt bike, a Honda CB350F or 400F frame, THIS KIT and the other pieces mentioned below laid out, the bike can be built (welding, etc.) in less than a day (not including painting or powder coating). Performance Specifications of the Version 1.0 bike in the picture are less than 240 pounds with fuel and approximately 55 horsepower. It is using a CRF450R engine. Design Cycle is finishing another prototype (Version 2.0 – the black bike) which uses this DCH450S kit with a weight (minus fuel) of 200 pounds as the goal. The kit is built in such a way as to allow flexibility in the way you want it to look (exhaust, radiator mounting, tank, tail, seat, etc.).

Please ask questions via email or phone PRIOR to ordering the kit. (850) 656-0014

Legality and local regulations are the responsibility of the buyer/customer/owner. Customer is responsible for safety of completed vehicle.

Specifications subject to change without notice!

You are bidding on a Design Cycle DCH450S Frame Mount kit. This kit allows you to put a CRF450R or CRF450X engine , swingarm and other CRF components into a Honda CB350F or Honda CB400F (front portion of frame is the same) frame/chassis.

A picture of the DCH450S Version 2.0 Frame Mount Kit is shown. The Frame Mount Kit includes:

Instructions with: pictures of actual build, CAD pictures of how the parts go together, parts list, recommended safety procedures, and more.
All brackets, sleeves, and hardware to install a CRF450R or CRF450X engine in a 1972-1974 CB350F or 1975-1977 CB400F frame
K&N air filter supplied with kit.
New All Balls Steering Head Tapered Bearing Kit included.
New All Balls Swingarm Bearing Kit is included.
Dual or Mono rear shock mounts are included in the kit. Brackets will need to be welded on to the frame (mono-shock) or the swingarm (dual shock) by a certified welder.
Rear brake master cylinder bracket is included. Setup to use stock CRF450 brake lever and master cylinder setup.
Kit allows for kick starting, electric starting and both features depending on your CRF450 engine.
CNC gussets & slotted plate to support bobber seats & mono-shock like on Version 2.0 (black/gold bike) ARE included

With this kit, Customer must supply:
· Street legal 1972-1974 CB350F or 1975-1977 CB400F frame. Those Honda bikes were street legal road bikes. We have a handful of titled frames that are available for sale. Just an FYI. This auction does not include a titled frame.
· 2002 – 2008 Honda CRF450R or 2005 – 2009 Honda CRF450X “car kit”. Possibly need the swingarm from the CRF, but you can use the CB350F/400F swingarm.
· Front end (see below for what will fit or bolt on). Many Honda sportbike front ends will bolt on.
· Muffler/Exhaust – stock CRF450 header works fine (no interference with frame), but muffler will be needed. See suggestions below.
· Lights (If needed) not included in kit. Keep wattage usage to a minimum.?
· Radiator mounts are supplied, but you may want to go to a single radiator below or in back with fan.
· Fuel tank – see suggestions below.

The CB350F/400F speedo gauge will work if you are using the stock CB350F/400F front end. Otherwise, we suggest a GPS for speedometer and check everything else before take off. If you want more than that, try one of the Trail Tech kits.

Options for fuel tank &/or tail sections:
1. Stock Honda CB350F or CB400F tank and tail will bolt on to the frame, because you are using a CB350F/CB400F frame.
2. We can build one for you.
3. You can buy one off the shelf at
4. Buy a fuel tank that has a 2.25″ or larger tunnel that is fairly short in length. The first two we have use old Harley Sportster modified tanks.
5. Make your own

Rear Shocks that will work on Dual-shock setup:
1. Progressive 12, 13 or 14 Series Shocks
2. Most shocks that have round bosses on both ends

Rear Shocks that will work on Mono-shock setup:
1. Stock CRF450 rear shock (although it is very long, so we don’t suggest it)
2. VFR400 (Japanese model)
3. CBR1000RR (depending on which seat configuration)
4. Progressive Shocks
5. CBR600RR (likely the best)

Honda Front Ends that will bolt on (inner bearing size is the same) Steering lock/stop will need to be designed (or just trimmed if you are using a CBR900 front end) on each, but easy to do:
· CBR600 F, F2, F3, F4, F4i
· CBR600RR (03-07)
· VFR800 (98-08)
· CBR900RR
· CBR929RR
· CBR954RR
· CBR1000RR (2004-2007 only, 2008 and later will NOT work)
· Others may also work

Exhaust systems that will work:
1. Stock CRF450 header with muffler, but tubing from muffler to header will need to be made.
2. You can fit a “MotoGP” style exhaust
3. Stainless steel flex tubing & muffler (as shown on Red/Cream colored bike…use your imagination!

Florida Buyers: You will be required to pay sales tax of 7.5% (Leon County) or your county’s applicable rate.


Free UPS ground Shipping to continental USA.

Returns: We allow returning the kit if returned in unused condition within 7 days.
Any questions, please call before bidding. Thanks for your business!

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