CB750K5 for the strip

[UJM]

Thanks guys

Stock tubes would be too low - the header would drag.

I believe these tubes are 12 over and they need 8.5" off, there are options.

Cutting them down is viable, but I've got the resources.....



"dj" supplied some timeslips from the past, for comparison:

CB 750 Turbo

60 Ft............2.216

E.T..............8.560

MPH..........90.638
_________________________________________________

1976 Red Kawasaki 900

60 ft...............2.241

E.T................8.905

MPH............79.894

Those made me feel pretty good about how well the bike was running, everything considered.

Pic's on the way.....

[SV650s]

Long live the SOHC CB750. Steve; you rock!

[UJM]

Originally Posted by MisterMike

Long live the SOHC CB750. Steve; you rock!

Thank you!

Here are a few pictures -

[UJM]

Hopefully there will be a video here soon.....

YouTube - 1975 CB750K Drag Strip Testing

[Igneale]

Nice video. You should get the forks cut, you have something happen that close to your face it'll look like this when you're done.

[scrat]

weeeeeeeeeeeeeeeeee!!!!!!!!!!!!!!!!!! or maybe...you could slide the forks back down and practice whoolies?

[UJM]

Well, I decided to bust into the clutch to see what was what.

Sounds like we may have the grunge match the first possible Wednesday, possibly the 22nd.

I had just posted a seeder on Craigslist and had gone to unload the bike from the van.

Got it unloaded, got the cover off, cable was screwed up in the lower mount, worked it out.

Then, the phillips head screws, ah, I forgot what pure crap the Japanese used for screw heads back them.

Immediately I went for the impact driver, ground the tip off a bit so it would bite, and it still rounded off screw after screw - and I was trying to use a pick type hammer with a pointed end - uh, never mind, this was not going well -

Then my cell rang, I had tried to call my wife earlier, she did not answer.

It was a call about the seeder, my phone sucks, I have a hard time hearing and understanding him.

He wants it, he is an hour away, we'll met in the middle, trying to work out all the details and - ANOTHER INCOMING CALL.....

Now I can not even hear the guy, I see it is my wife, great -

I wrap up with him quickly, go to answer her call - she hung up.

I'm sweaty, aggrevated - and the house phone rings....

It's my wife, "just checking in" - I mentioned I tried to call her earlier because I needed something, she giggled she did nto even have her phone turned on -

AHHHHHHH!!!!!!!!!!!!!!!!

Anyway, I put the bike together enough to pull it in the garage, yes, like a true idiot I was working on it in the sun, in the driveway, where all could see - and the guy across the street has a little dog that was bark bark barking for HOURS from inside, WTF....

OK, maybe i need to restart my day.....

A nice drive in the Porsche

(It better not break down)

[gpzTurbo]

when is the grudge match?

[UJM]

I'm hoping for the 22nd or the 29th - probably the later.

Should be a good race.

[UJM]

Thank goodness for eBay!



Gotta love "free" motorcycles........

[UJM]

Here are the plates -
Fibers smelled as bad as they look
2 of the metals warped.....

[UJM]

All the clutch parts have been in the garage for a few days, finally made time to re-assemble it.

Replaced the fibers (NOS EBC/$40.00) and the warped metals - glass beaded the metals, they all cleaned up very nicely.

10% stiffer springs with extra special attention spent on tightening them -

Replaced the phillips head screws on the cover with allen heads, adjusted it all out, so far so good.

Tomorrow, I'll pick up some gas (50/50 Unleaded Premium and VP-110 which is leaded) and take it for a test ride.

Spoke to the owner of the RD350, he was singing a song of a high speed miss, the points not being set right but he set them earlier, jetting wrong, blah blah blah -

But, I think he is B-S'ing because he said he would make it to the track this Wednesday night -

Maybe the ultimate grundge match is about to take place -

Hot, sure it is hot, and humid.

But I'm not making any excuses folks, I'm going for one reason and one reason only - to have fun!

Oh, and to win, for sure -

[Bigdaa]

Cool bike, uj.

[Etroze]

Hope your match goes great sounds pretty interesting. ive seen Scrats little 450 out at the strip and it goes like a raped ape in an 1/8th mile even when the front wheel was in the air and his feet draging half way down the track.

[UJM]

Thanks guys

Pulled the bike out of the garage, added fuel, started second kick.

Took off down the street, went to a nice long straight, opened it up on the way back, ran OK, needs to be warmed up to run right - then I saw the cop.........

I had taken it to 8500 in 4 gears, coming down an incline, there he sat at the stoplight.

Open 4-1 headers draw attention.

So does a license plate that expired in 1993 -

Luckily, the light changed and he had to go - far enough to get caught in the divided road section, good enough to give me time to whip it on home and park it in the garage -

Think I'll buy four plugs tomorrow and call it good.

[UJM]

Well, the local track was not open for test and tune night, quite the bummer, but there is always next week.

When I stopped in at "the shop" that afternoon, I caught the owner (BJ) of the RD350 in action -



Hummmm, did not really look like the old stock street legal RD that I remember -

Running struts, lowered the forks, flipped the shifter over and is using the passenger pegs - had the carbs off for a full rebuild, a lot of action.....

And he is considering running "optional" body work and tank that I have to admit I approve of -



And later, I found out about some additional help he was being given -



Yeah, caught in the act. That gentleman sitting there is one of the best motorcycle mechanics in the central United States, IMHO. He was setting the timing for BJ - dial indicators in action, oh yeah, I feel like I am being snookered here.....

I asked again about the porting and pistons - "Stock, completely stock" I was told.

"Freshened it up, that's all".

Maybe next Wednesday will be the day, the grunge match needs to take place, but, maybe with this window of time, I can make a few other little tweeks to the old CB750 as well.........

[Simpson]

I am so into this thread....

[secondchance]

nice the family likes to go watch ... nothing better

[UJM]

Is tonight the night?

I hope so - it is the weekend before the 20th anniversary of the track.

The owner of the track is racing this weekend, and you can bet your boot he will want to make a few passes before his races this weekend.

Is BJ ready?

If so, what else did he do to that old RD350 of his????

Is tonight the night?

[UJM]

Immediately after unloading the CB750 and the initial firing up of the engine, the bike died.

Just stopped running, thought it blew a fuse.

Thanks to a couple people, we tracked it down to a corroded connector in the wiring harness, things started looking up.

The race, it took place.

Yes, it did.

Arriving early, I was able to make a few passes to get the feel for the new clutch and make final adjustments.

First pass, out of the box, I red lighted with a .432 reaction time (sign of things to come?) , but ran the following:

60' = 2.123 8.715@79.92

One test run was against a big bore Kawasaki "real deal" drag bike - why I lined up against it, I'll never know, maybe just because WHY NOT!

This time, the CB750 ran 60' = 2.0459 8.635@77.58

Kawasaki: 60' = 1.403 6.133@110.29

I over-rev'ed the bike in first, thus the lower MPH - check the reaction times:

Kawaski @ .854 and me -

.592!!!!! (.500 is perfect)

I had him on the launch, but he quickly handed me my lunch, that is when I screwed the pooch on the 1-2 shift.

Like it would of mattered anyway! Good fun, the Kawasaki was ownered by Bob from Lincoln, nice bike, great guy.

One race was against a hopped up 4 wheeler, another Kawasaki -

CB750 60' = 2.218 8.785@80.35 (.780 reaction time)

ATV 60' = 2.401 10.63@60.00 (1.059 reaction time)

And then a 919 - WHAT!!!!!!!!!

Ah, the memories, this one was a late model ruby red edition with a 160lb rider.

How bad would I be smoked? I did not care, I was going to give it my best.

919 60' = 1.924 7.351@98.90 (with a .826 reaction time)

CB750 = 60' = 2.076 8.611@80.35 (.657 reaction time)

Good, no GREAT times!

At about 8:36 I called the owner of the RD, as he had not shown up yet -

He answered, and was at the gate, on his way in.

He parked next to me, I say the round polished aluminum fuel cell - reaching to open the cap, I wanted to smell what he was running, he slapped my hand away - alcohol?

Nitro?

Wait - no headlight, what - well, no matter -

And I have to appologize, I have to take my son to basketball camp now and go to work for a bit -

I'll be back as soon as I can with the results of the 8 races we had, the 1975 CB750 versus the 1975 RD350 -

with pictures and hopefully some video

[UJM]

I'm sorting through a lot of data, pictures and video - plus phone interviews for jobs and playing MrMom - I'll get as much posted as quickly as I can

Here is my launch against Bob from Lincoln -



And - drum roll please - a couple shots of the RD350 and the CB750 lined up and ready to rumble -

[UJM]

OK, here are the round one timeslips



It is rare that I redlight, this was not a good start to the night.

Wanting to win too bad came at a price, and that was jumping the light-

The last two races of round one, the RD350 rider was waiting for the CB750 to launch, using that more so that the christmas tree, a good move.

Round One of Two:

RD350 3

CB750 1

[UJM]

Round Two timeslips -

Take your time to study the numbers, folks, it does not get much better than this -

[UJM]

Well, the RD is getting an extended swingarm and some other "changes" that may make it very difficult to complete with the CB750 as it is.

We'll see......

[Simpson]

Refer to my comment in SOHC.

[motohorseman]

I'm glad this thread is still around, good memories of that experience!