Metrics are what you call new japanese crusiers. Old hondas are not metric bikes but are vintage bikes, like old bonnies and WLA harleys. Just call them soul machines. I mean, nobody goes around calling old triumphs witworths? right?quote:
Hey guys, I'm new to metrics...I've been into American V-twins for the last 5 years or so. Choppers and Customs mostly, anyway I recently got turned on to Cafe Racers, really dig the style and at the same time looking for something as a daily rider to get back and forth from work and scoot around the city. So I've decided I'm going to build a Cafe Racer for my daily rider. I want to use the Honda CB750 as a base, thinking about an early to late 70's model. So my question is there any certain model or year that is better then another year to build off of? Maybe some years have better handling then others or better drivetrain/engine then others? Any help would be much appreciated.
SOHC cb750s were made from 1969 to 1978. They rpoduced in the range fo 53-68hp depending on the year and were made in three basic models: the K (standard), the F (Supersport), and the A (Automatic, yes as in automatic transmission).
The 1969-1970 (K0) bikes are the lighest and were at one point considered the fastest. They made the cb750 reputation and their looks as a stocker are unbeatable. Unfortunatly these are usually the most expensive cb750s and they are somewhat fragile.
The 1971-1972 (K1, K2) fixed a lot of problems with the early bikes, and their look was a little sleeker. They still fetch a high price and are considered the last of the fast K bikes.
The 1973-76 K bikes (K3,K4, K5, K6) are probably the mose refined K bikes. Honda figured out that the cb750s fragile nature was due to the power output and lowered it to 58hp. Most good condition cb750s will make between 53-58 rwhp. The advantage is that they have the earlier bike's shape but rock solid reliability. I personally own a K5 and that bike is an anvil ( I also own a K3 with equal reliability). There are minor changes throughout the bikes but most of the k3-k6 bikes have a lot of parts changeover so spares are easily available. These are the engines you need if you are going to do an 836cc conversion.
the 1977-78 K bikes (K7, K8) are more refined. The bike got heavier, the power output went up and the addition of a 630 chain made the bike less prone to breakage. Most people think these are the ulgy cb750s and therefore they sell for the least amount and people like to chop them up. Anything that makes these porkers lighter is a blessing
In 1975 honda introduced the SS (F bike). All F bikes have a read disc brake instead of a rear drum. The 75-76 (F0, F1) was basically a K bike with better carbs, a rear disc and bodywork more like a kawasaki triple or suzuki gs with a tailsection and stepped seat. These are the only cb750 hondas to use a rear disc on spoke rims so lots of guys building cafe bikes look for these rearends. The 1977-78 F2s, saw a lot of improvements. The engine hp was boosted and the bikes are as fast if not faster than the early cb750s. They got mag wheels and the ability to run tubless tires, and also the best brakes ever put on a SOHC 750 (dual disc up front, rear single disc). All F bikes use a 4 into 1 exhaust (instead of the K bikes 4 into 4) which helped ground clearance but you still run out of room on the right side and the mufflers are heavy.
The A bikes are hondamatics (1976-78). They have no clutch or tach and the brakes are on the handlebars (one is a parking brake). They have the strongest bottom ends and a lot of cb750 racers used to use the A cranks in K cases to build strong race motors. They come with aluminum rims on the stock cb750 hubs (a GW part bin raid) so they make excellent parts bikes for a cafe racer looking for DID aluminum rims on the cheap. Other than the novelty factor they really aren't that cool and are probably the heaviest cb750. I had a friend who had a 900cc kit in a hondamatic and that bike was cool because it did burnouts, holeshots, and chirped when it shifted. Honda made the automatic a 400 in 1979 because the cb750 was too heavy for the women who wanted to ride it.
A couple of sites to check out:
there are tons others but this will get you started. the SOHC forum has a parts list thread and can tell you where to get the best gear for the bike.
I'm sure i missed a ton of info so feel free to chime in.
Don't rule out the DOHC supersports of 1979-1982. They can be had in 750, 900, and 1100 cc flavors, have great brakes and bodywork modeled after the BOL D'Or endurance racers. They make 80-100 hp and are every bit as reliable as the SOHCs provided you keep up on the maintenance. I own a 1979 750 and a 1982 900 and they really the best of both worlds, vintage riding expirence with modern brakes and speed.
check out www.cb1100f.net
Edited by - Geeto67 on May 15 2006 4:03:47 PM