id recommend suspension before motor but that's just coming from my car modding background, always better to be able to handle before speed, rear shock is probably the easiest upgrade if you get one that drops in and if you want a wider tire without modding post kat rim 4.5"

I'd look at brakes first, then suspension, riding skills and finally, more power if you still feel you need it.

The stock brakes are really pretty decent but chances are you've never done much to them. Rebuild the calipers and MCs, replace the lines with new, braided lines from G&J Aircraft Brake Lines and install some new sintered pads. You'll definitely notice the difference and it'll only run you about $200.

As for suspension, I'd get with Tmod. He can guide you through upgrading your forks and replacing your stock shock with one that actually controls the rear end properly. he can also help you to tweak the suspension to match your weight and riding style.

When it comes to power, the pre-750 actually makes pretty good power. It's not anywhere near superbike levels but you can work around that pretty well by learning to manage the power it does produce. Some of that is riding ability and some is energy management. A weekend at a track school can help out there but I wouldn't advise paying for that until you've got the brakes and suspension in tip-top condition.

Im a nuts and bolts guy so doing the work will be fun and relaxing to me. I have bought a new harness and CDI from a member here (practically given to me, very appreciated) and I have decided to do a complete carb rebuild to get those puppies right once and for all. Worried about my airbox leaking around the boots but way down the road. I totally agree with making it stop and handle better before the engine. With never modding a bike I am just worried its gonna cost me due to my own errors and I am making a conscious effort to reduce that. I am pretty well set on the B12 though as I love a good sleeper. I once had a chevy chevette with a built 305 that terrorized mustangs lol. I just sold my '72 360 Duster because I want something new to learn, besides electrical phooey on that. I have no doubt when I am bored of it I will sell it and do something else "crazy".

The B12 or 1127 motors won't have any major effect on the chain alignment. Both were designed with use of the 5.5" zuki rims in mind, and the 3.5-5.5 Zuki rims pretyt much all share the same spacing on the sprockets from centerline.

The r6 shock is a great option for low cost improvements. It does lower the bike though though about .75". For me... this doesn't work so well in the heavy curves. I went the route of using a Tmod modified B12 shock. It raised the tail of the bike by 1.75" higher over stock. This not only gave alot more clearance, but the new geometry gives a bit quicker turn in as well for the curves. This worked well for me.

Unmodded you can use 4.5" rims and 160 tires would give a really good performance profile for that rim. Larger than 4.5" rims and no matte what shock your using... the swingarm just really isn't wide enough for the proper tire clearance.

I agree with the prior mention... the upgrades listed for the braking (rebuild and new lines) will give you really well performing brakes. If you go with the USD front forks, then you will have to look at using the brakes and wheel for those anyways. The Kat stuff will not work with those forks.


If it was me... the route I would go...

Modify the swingarm for the 5.5" rim and rf9 armless caliper bracket setup. Determine the tail height you want for the bike as compared to stock. If your going higher, go b12 shock, same height... early 90s gsxr shock, lower... go r6 shock. Which ever you pick, have Tmod rebuild and mod it for your bike/riding style/weight. Also have him redo your kat forks with new springs, modded damping rods, and emulators. Rebuild kits for the master and calipers for the brakes. Versah HH pads. Stainless braided lines. Consider either b12 or 1127 motor based upon avail and price. I've seen alot more of the 1127s for alot cheaper than the b12 options.

Your looking at aprox the following for the mods avg costs...

Brakes under $200
Swingarm around $300
Engine aprox $500
Suspension aprox $700... and worth every penny.

So your looking at $1700 to mod the bike you already have and end up with a bike you can't sell for much more than that. So if you do it, keep in mind it's not a money maker... it's something you want to keep or loose $ on.

Krey

That's pretty much the definition of a motorcycle, isn't it?

Only way I've ever made money on a bike is by picking it up almost free, putting a bunch of work into it to get it running right and then selling it before I can be tempted to put any real money in it. If I hang onto it long enough to start thinking of it as mine I'll start throwing nicer bits at it and end up with a bike that's worth less than what I've put into it.

Another low cost minor performance gain is lose uneeded weight ie center stand and 520 conversion

Minor is the key word there... as in so minor you won't be able to notice the difference. Not one bit... not even at all.

Krey

i noticed on the 520 conversion a little quicker acceleration the kickstand not so much

Thanks for the input krey I was hoping you would pop in on this one. Here is where I stand with the swingarm though. I have no welder and all the shops I have been asking want roughly 300 for the welds,thats not mentioning buying the SA/rim and all the goodies, stupid and outrageous. Is there a better way, say have one of you guys paid to do it or should I just stick with current stuff? As afar as the rear shock goes I really dont want higher because I am only 5'10" and feel comfortable with the seat height now. I dont use the center stand so ditching it is no big deal. I do like the 520 conversion. I am not to worried about making money on it if I sell it either, its a big boy toy to me. Performance wise how is the 1127 to the B12?

the only suggestion on the modifying is make friends with someone who can weld lol, short of that remember that on something as crucial as the swingarm you don't want a second rate job so a little extra cash on something that could very well be holding your life doesn't sound like a bad idea, but 300 does sound a little steep, i've never paid to have something modified for me then again i grew up in an auto shop learning to weld

Seriously, it's all in your head. Numbers at the track and dyno don't lie. If you can feel >1HP and a couple pounds less, you need to be racing MotoGP.

i didn't say there was a HP gain just slightly better accel because your dropping rotating mass, there is in fact science behind it, again i said minor, but doing little things do add up, also I'm comparing this to mine when it was stock and my buddies which was an 89

Again, if you can feel less than 1 HP during acceleration, you need to be a professional roadracer. I'm absolutely serious when I say it's in your head.

I guarantee that if I put you on identical bikes, one with 520 and one with 530, you couldn't tell the difference. Bottom line, on a heavy bike like the Kat, it's a bad idea to shrink the chain size. The money you save by cheaper parts gets used up in less longevity. The power/performance gain is virtually nil on a 500 lb bike.

I like this, a pro/con approach. Your saying a 530 outlasts a 520. The reduced mass is also negligible. Other than cheaper parts that wear faster there is no point. Right?