KZ 650 project

Bradykull wrote: Any ideas on rear shocks? I've come across a nice set of ZRX shocks that are 14"... I've read on hear that they will obviously be sprung to heavy for a little kz650... And a bit long...

Are they adjustable enough to make work?

Thank!

Brady

Heavy? Why? Ed

I would like to keep shocks around 300 bucks. I'm thinking I can get something usable for that price.

Looking for a little bit of both, high speed is kinda out of the picture until the stocker 650 motor gets worked this winter.

But let's just say I'm looking too, "stabily corner, at high speeds.".... Eh? Eh?

I've been chatting with Todd Attebery from Z1works and he has been filling me in on some of his trial and error findings over the years... Biggest one being forks. He has found that the 07-08 ZX6r forks are actually 2 inches longer than the 05-06 forks that I have... (Just my luck...)

So going back to what you said about ride height! I will be either... Buying 07-08 forks (if I can locate a pair), turning some internal fork extensions on the lathe (shit ton of work/time), or buying fork extensions from a company I found on the web (400 bucks... Knife threw the heart)... Hopefully this will keep my rake and trail at bay. And allow me more rear shock options

I will be looking into that book, sounds like an awesome read for any motorbike enthusiast!

Strictly going off the fact that the stock ZRX weighs about 495...

Kz650 weighs 30 pounds less than that. Not to mention the weight I'm dropping by using lightweight modern sport bike wheels and front end.

Maybe a bad choice of words on my part, I should have said, "sprung heavy".

What's your take on it Ed?

DOHC wrote:

DoctoRot wrote: I would pay more attention to the swing arm angle, 10-13 degrees is considered the sweet spot.

Can you explain this a bit more? Degrees between what? And under what conditions?

if 0 degrees is parallel to the ground. a straight line between the axle and pivot point should be 10-13 degrees while the bike is unloaded. Typically longer swingarms can have more angle than shorter ones. There are many factors that will dictate the exact angle, it will change depending on application and rider preference. This angle has to do with anti-squat, and the front suspension unloading when exiting corners . Here is an article explaining the factors better than I can.

www.cycleworld.com/sport-rider/how-motor...nts-impact-traction/

I wouldn't worry about a stock shocks weight rating too much, there are other factors at play such as front/rear weight bias that can affect how stiff or soft a shock feels. That being said, most factory shocks I have come across are too soft except for the lightest of riders. ZRX adjustable shock has adjustable preload/compression/rebound, none of these will be of any help if the proper sag cannot be set. You will need to re-spring the shock if you cannot set sag correctly

$300 for shocks is a drop in the bucket as far as performance shocks go. you can get some OK shocks for that money that will perform fine for average street riding but nothing I would call a performance shock. I think Hagons cost even more than $300 now. Getting a ZRX shock and having it re-sprung and possibly re-valved by Race-Tech is probably one of the cheaper ways to get a shock setup for your application.

Understood Doc! Thanks for all your help! Pic coming soon for dry fitment process!

Bradykull wrote: Strictly going off the fact that the stock ZRX weighs about 495...

Kz650 weighs 30 pounds less than that. Not to mention the weight I'm dropping by using lightweight modern sport bike wheels and front end.

Maybe a bad choice of words on my part, I should have said, "sprung heavy".

What's your take on it Ed?

With both bikes weighing close to the same amount(+/- 30 pounds) and the ZRX shocks being adjustable I would expect those shocks to work ok. I guess if you plan to reduce the weight of the KZ650 by a bunch, maybe other shocks would be a good bet, but they may be expensive. Have you considered having shocks tailored to suit the application? Hagon might be able to do that for you, but I don't know how much money they might charge. Ed

www.hagon-shocks.co.uk/

BTW here is a trail calculator that i have used before

rbracing-rsr.com/rakeandtrail.html

Well! 650 project quickly became a 1000 project. Found a parts stash here in PA. And got a killer deal on basically two full kz1000's.