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Discussion Starter · #1 ·
Well, finally got it on the track. I was very pleased--VERY!! I ran 13/37 sprockets on my very first run (up and down the road) and the tach was pegged past 12K but it was still pulling strong. I changed the gearing to 15/37. I decided that tach was junk so, I switched it out at the track for one off my 1969. That tach stopped at 8500 and the valves (or points) were floating. Best I could do was 92MPH. So, that tach may well be junk too. In any event, something is wrong-- I'm going to have my buddy use his induction pick up to compare his RPM reading with the tach. Plus, I'm going to try swapping cables to -- just maybe-- see if that's the problem. Next step is an electric tach from Vapor (that's all I recall-- they have one that gives RPM, Speed, hours, engine temp, stop watch, shift lights, rev limiter and other stuff I won't use) for $119.00. I may also install Bore Techs electronic ignition too ($389.00--ouch!!).
Saturday 04/24, started in the rain. Brand new race compound tires-- still had the mold flashing on em. I went slow, keeping in mind I had no clue how these tires would work-- wet OR dry. Plus, they needed to be bedded in. 3 laps later, on a soaking wet track, light sprinkles, I picked up the pace. The tires stuck like glue. I was passing liter bikes in the corners like they were fence post-- 3,4,5 and 6 at a time. Of course, once they got on the straight, they exhibited their main talent, twisting the throttle. They would blow by me at 140-150 MPH.
I wore a bright yellow jersey to help be seen and not mowed down.
Well, that's enough on the story-- bike sounded good, ran good, handling wasn't what I wanted-- a lot of jounce in the corners-- gotta work on that. Tires were great-- even better once the track started to dry. I even moved up to the Intermediate class.
Here's a vid of my first outing in that class right after lunch. I'm in that yellow shirt, right at the start. That's turn one, two and then he passes me in the left hander-- 3. He doesn't catch me again for another 7 1/2 minutes and 6 laps.


Here's a picture of me-- first start up after 19 months, getting ready to run down the road for the first time since I bought it. Still has the 38 year old tires on it!


Here's my rear tire after two 20 minute sessions. I was very concerned about the wear-- especially in the center, but a couple of AHRMA guys say it's normal.


Next stop: Blackhawk Farms, May 22ND for race school so I can get my license. Then, June 12TH at Road America for my first race!

Anybody have (or ever heard of) a 16 tooth front sprocket??
 

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Discussion Starter · #2 ·
And--FYI, those are not your pipes JeyLux. They are resting peacefully on the top shelf of my parts bin!! Still complete and intact!!
:D

June 19/20 I'll be at Grattan-- about a 2 hour ride from you-- hope you can come out. You WILL enjoy it!! Vintage biker heaven!!
 

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The bike looks great! Have fun and be careful. I've been to Putnam a couple of times and it's a fun little track but great for the 450 although the front straight me be a bit long.

What kind of tires are you running?
 

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Discussion Starter · #4 ·
Race compound (non DOT) Avon Am18 90/100X19 front and AM22 110/80X18 rear.
Yes, Putnam's straight is long-- but not as long as Grattan's and from what it looks like, Road America is going to be a high speed track.

None will compare to Daytona though!!
 

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WOZERD, I'll be at RA this year too... as a viewer, not a racer. you've got a great looking bike, man, good luck with your run. danWI
 

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WOZERD said:
I ran 13/37 sprockets on my very first run (up and down the road) and the tach was pegged past 12K but it was still pulling strong. I changed the gearing to 15/37.

Anybody have (or ever heard of) a 16 tooth front sprocket??
Holy cow, I'll bet it did pull hard with 13/37 !!!
If stock is 15/35, then "stock" equates to a 16/37 (rounding off) so your 15/37 is still a touch low (relative to stock). 13/37 would be real low, like 12.2/35 or so.

I had the same problem with my mutant 450 - the stock CB400T wheel I use has a 37-tooth rear.
I ended up with 17/37 - not sure what sort of balance between top end and acceleration you're after.
I'm not on the track, but I didn't notice much drop in acceleration with the 17 - takes a bit more clutch from dead stop, and buzzes less at speed though.

16 and 17 tooth fronts are commonly available......17 is about as big as will fit in that area I think.

I'm jealous - that looks like too much fun............

More, please.
 

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Discussion Starter · #9 ·
Bill,
Where would you suggest I look for a 16 tooth? I think I've seen em on E-bay. but not now.

It pulls nicely but, like I said, either it's floating the valves or the ignition is breaking up on one tach at 8500RPM. On the other tach, it's saying 12000 RPM and still pulling hard.

The 15/35 stock gearing comes out to 2.33 ~ 1
a 16/37 would come out to 2.31 ~ 1
Not much difference but, if I need to, I can even go to a 16/35 (for, say, Daytona) plus, it's easier to swap front sprockets and--I am just that lazy.

I just can't believe it's pulling those gear ratios! my other one won't pull redline (I think it's red line-- the needle bounces around like a fat girl on a trampoline) off a cliff!

I am currently running 150 mains. Up from the K5 stockers of 145. The plugs are nice and tan. I have velocity stacks with nothing but screens over them (to keep out small children, birds ETC) and virtually straight pipes-- I welded "shorties" on the ends. They have a packable, removable baffle (perforated tube), but nothing you could actually call a restriction. Gotta say-- it's loud! I scared quite a few squid's on sport bikes when I would come up behind them!

And, yes-- what's that saying? "More fun than one man should be allowed to have!"
Especially for a 62 year old fart like me! It has been 5 years to the day since I've been on the track-- even took time out for a stroke, a carotid by pass and 3 stints but, it all comes back-- just like riding a bicycle! Or, should I say motorcycle?
 

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WOZERD said:
Bill,
Where would you suggest I look for a 16 tooth? I think I've seen em on E-bay. but not now.

It pulls nicely but, like I said, either it's floating the valves or the ignition is breaking up on one tach at 8500RPM. On the other tach, it's saying 12000 RPM and still pulling hard.

They're usually on EBay, but....

I know Bike Bandit has 15, 16, & 17 in stock - can't remember how much, but it's not much.
They also have rear sprockets.

I seriously doubt that any stock-ish 450 could survive 12,000 rpm for long.........
You're probably not interested in idling anyway, so I say as long as the plugs look good and it runs strong, you're done with the engine.
A good running 450 can get close to an honest 100 mph, but will get a little snakey if it's not set up right.
Sounds like you need to work on suspension and gearing now.
You have good swingarm bushings, yeah??
 

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Discussion Starter · #11 ·
OH YES!! Thanks to you!! It took me six months of filing, hammering, drilling but, I've got new swing arm bushings!! :lol:
 

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Discussion Starter · #13 ·
Thanks Bird.
I would really like a 16 before going to 17-- 17-- wow-- that's tall! I might do it and switch back to that 37 tooth rear-- but, I'll probably have to add more chain links!
I took it out today and did a back road burn. Marked off 2500 ft and hit the start point at around 40. Had my son's GPS hooked up. Very disappointed.
85MPH at the end of the 2500FT mark. :(
This is with stock gearing-- 15/35.
One tach still refuses to go past 8500RPM. The other jumps to 12 especially in the lower gears. I noticed after a bit it steadies and -- is somewhat accurate-- I guess. it showed just under 10K as I crossed the line.
I had high hopes, after being trailed on the track and told 90/92MPH, that going to stock gearing would give me a higher top end even though it took a little longer to get there. That just goes to show how off even modern bike speedo's are.
Plugs are light tan (as opposed to simply "tan") -- maybe I could go one size jet higher but-- if anything, that will slow me down on top end.
Full advance timing, with a light, is spot on. Engine is tight.
I don't know-- I really thought I was going to see 100MPH +
 

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that was awesome!!!!
I'm confident my un-restored 450 K-7 will do 100mph based on the fact it hits 62 mph at a mere 5,500 rpm.
if red line is 10,000 I conclude it can do it; saw my mechanic hit it hard last year and he lost me in my car!
bike look like it handled on rails! I was impressed. mind you, it depends who's driving it.

my father, with extensive knowledge in physics believes I am over-working my motor. How so?
I tried some combos and my bike won't hit 62 mph in any lower RPM than above.
what does he know, he don't even ride. ha ha.
any insight? if red line is 10,000 I HIGHLY doubt 6,000rpm is over-working it.

tires: I have old dunlops on mine but they have tread, a little weather checked and feel hard. quite hard.
They passed inspection and since I ride 45-55mph I don't foresee replacing both of them just yet.
but maybe replacing the rear next season could be smart. saving $ on safety might not be prudent.
 
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