Author Topic: 1978 CB750K — Post 836 OIL PRESSURE - Hopefully Good!? (Read 251974 times)

SKTP · « **Reply #1225 on:** February 07, 2018, 11:54:57 AM »

So the motor is out again and the head and jugs are off.

I considered a full-on port and boring to 836cc, etc....but that just gets out of my price range fast (new rods, piston, bore, cam, port, etc = EXPENSIVE)

But since it is apart and there will be a MILD PORT...are there any GO FAST mods that are somewhat economical that I could do? A MILD CAM has been mentioned ($200-$250ish) would that be a good idea? (I already have APE valve springs) its a stock bore...open to all suggestions

SOHC4 Cafe Racer Fan · « **Reply #1226 on:** February 07, 2018, 04:06:14 PM »

You could always buy my Wiseco 836 kit, CX7 cam, Stage 4 ported head, HD chains, tensioners and studs, lightened and balanced crank with Cycle X Super Rods, and balanced rotor.

Jerry Rxman Griffin aka MuthaF'er · « **Reply #1227 on:** February 07, 2018, 04:13:14 PM »

Put your rods money into your head. You should be safe at 836 with stock rods.

SKTP · « **Reply #1228 on:** February 07, 2018, 04:24:39 PM »

OK. So other than PORTING, there's not much to do to "GO FAST" a stock bore?

Don, your parts are worth more than my entire bike!

seanbarney41 · « **Reply #1229 on:** February 07, 2018, 05:15:27 PM »

sure...get a cam...but the really good cams require more compression than stock. Upping the compression is good for several ponies in it's own right...but the cheapest way to raise compression is new pistons, and then you might as well be doing a big bore!

Seriously though, every part on you bike can be tuned for more power. Don't just fix broken stuff, improve it.

Fast, Dependable, or Cheap...you only get 2 out 3. Which do you want?

SKTP · « **Reply #1230 on:** February 08, 2018, 01:10:14 PM »

PISTONS $429 http://www.dynoman.net/engine/pistons/honda.html

RODS $599.00 http://cbrzone.com/sohc.html
or $525 http://www.cyclexchange.net/Cranshfts%20and%20Connecting%20Rods%20Page.htm
Let's say $550ish

STUDS $165 http://www.cyclexchange.net/Cylinder%20Studs.htm

CAM $230http://www.cyclexchange.net/camshaftpage.htm

Then Boring, Porting +Gaskets, writs pins, etc...$300 - $1200ish?

Ballpark that's already ballpark-ish $2000 in just parts and machining

Am I wasting my money doing a port and cam? I am after reliability and longevity

Going to call Cycle-X for their thoughts

SOHC4 Cafe Racer Fan · « **Reply #1231 on:** February 08, 2018, 02:00:45 PM »

To get the best gains out of a cam, you will want to port it and go with higher compression pistons.

Porting will help in any case -- even if just to remove casting marks and improve flow.

SKTP · « **Reply #1232 on:** February 08, 2018, 03:06:18 PM »

http://draftcycleworks.blogspot.com/2010/09/porting-honda-head.html

Stev-o · « **Reply #1233 on:** February 08, 2018, 03:45:42 PM »

Some of the other guys may balk, but spending a lot of dollars on trying to get a real-go-fast CB750 may disappoint. It wont be fast compared to the Duc you used to have.

Would I spend $2K to have my CB go as fast as my Kaw 900? No way!

Just bore to 836, get it reliable and leak free...

SKTP · « **Reply #1234 on:** February 08, 2018, 05:20:57 PM »

Pretty sure I am just going to get it ported, tuned and the front end RaceTech'd...

MauiK3 · « **Reply #1235 on:** February 08, 2018, 06:42:52 PM »

Not to hijack......
Steve-o, what Kawa 900 do you have, is it restored?
Steve

SOHC4 Cafe Racer Fan · « **Reply #1236 on:** February 08, 2018, 09:16:55 PM »

Quote from: SKTP on February 08, 2018, 05:20:57 PM

Pretty sure I am just going to get it ported, tuned and the front end RaceTech'd...

It is equally if not more important to improve the handling (and brakes) than increase your power.

That's why the RC51 has such great stock brakes!

Stev-o · « **Reply #1237 on:** February 09, 2018, 07:05:03 AM »

Quote from: MauiK3 on February 08, 2018, 06:42:52 PM

Not to hijack......
Steve-o, what Kawa 900 do you have, is it restored?

1975 Z1 900, I restored it 4-5 years ago.

SKTP · « **Reply #1238 on:** March 01, 2018, 03:14:18 PM »

Just shipped my forks to Racetech to get Emulators and new springs!

http://racetech.com/

SKTP · « **Reply #1239 on:** March 13, 2018, 01:06:36 PM »

Since I have grown tired of annually rebuilding my motor, I called in the pros and couldn't be happier!

#professionalhelp

SKTP · « **Reply #1240 on:** March 22, 2018, 03:04:04 PM »

Race-tech is saying I need new "inner fork tubes" to guarantee the forks not leaking. They are saying they will use Forking by Frank and that the tubes are $375...That is crazy high don't you think? http://franksforks.com/

I just talked to the Race Tech sales person and they are saying the Frank's Forks are built from scratch and will take 3 weeks...That sounds insane for stock fork tubes. Any tips on where to buy 1978K for tubes?

Cycle X?
http://www.cyclexchange.net/fork_tubes_and_accessories.htm

SOHC4 Cafe Racer Fan · « **Reply #1241 on:** March 22, 2018, 04:13:29 PM »

Quote from: SKTP on March 22, 2018, 03:04:04 PM

Race-tech is saying I need new "inner fork tubes" to guarantee the forks not leaking. They are saying they will use Forking by Frank and that the tubes are $375...That is crazy high don't you think? http://franksforks.com/

I just talked to the Race Tech sales person and they are saying the Frank's Forks are built from scratch and will take 3 weeks...That sounds insane for stock fork tubes. Any tips on where to buy 1978K for tubes?

Cycle X?
http://www.cyclexchange.net/fork_tubes_and_accessories.htm

I always buy from Frank if the bike is a keeper. The chrome they use is premium. It's funny though. You send a check to Frank after placing your order on the phone with his wife. Write down your specs and send it with your check. I can see why Matt Wiley and the guys at Race Tech use Frank's fork tubes; that way, they don't have to worry about any quality issues on the parts.

Cycle X stuff will work okay.

SKTP · « **Reply #1242 on:** March 22, 2018, 04:59:26 PM »

I was all excited about the Race-tech thing. I sent them my forks on March 1st (today is March 22nd). I was originally told 2-3 weeks turn around. For springs, emulators and installation it would be $584. Which I thought was high (compared to buying progressive springs and doing in the garage), but whatever nothing too crazy. Now they want me to buy $375 fork tubes making the total $959.37 and adds another 3 to 4 weeks. So 2 months and a Grand for a fork rebuild. Am I wrong to think this is not cool?

seanbarney41 · « **Reply #1243 on:** March 22, 2018, 05:13:57 PM »

You will think it's cool when you ride it...lots have just bought the parts and done themselves. I did it in a long afternoon. Did your forks leak before you sent them. If not, maybe tell them run what ya bring.

754 · « **Reply #1244 on:** March 22, 2018, 06:43:37 PM »

ImO if FbyF are not hard chromed you are better off with stock.
The aftermarket forks I measured a few years back, were not always on size.
Tell them they have to guarantee they are plus or minus 2 thou..

I checked they are hardchrome, so are 77 and 78 fork tubes for 750.
As far as I recall, FbyF used to use decorative chrome, back in the day..

SOHC4 Cafe Racer Fan · « **Reply #1245 on:** March 23, 2018, 04:43:29 PM »

Forking by Frank tubes are hard-chromed. For at least the last 6 plus years.

SKTP · « **Reply #1246 on:** March 23, 2018, 07:01:37 PM »

http://www.racetech.com/page/title/FTNK%20Fork%20Tubes

I went with these tubes. They had them in stock.

754 · « **Reply #1247 on:** March 23, 2018, 10:50:06 PM »

How much and what color did you get ?

SKTP · « **Reply #1248 on:** March 25, 2018, 09:27:59 AM »

Too much and chrome

SKTP · « **Reply #1249 on:** April 09, 2018, 10:55:59 AM »

Put almost 200 miles on it this weekend...Ring break-in so I am staying pretty mellow and under 5000rpms...looking forward to seeing what it can do now that it is together properly

(These are from the initial test drive just down the block and back. I am not a squid).

New things to-do list:
- Mount front fender lower in the back.
- Get a new headlight bulb that is brighter and works with my bucket/ring.

News:

Author Topic: 1978 CB750K — Post 836 OIL PRESSURE - Hopefully Good!? (Read 251974 times)