Author Topic: Cobra motor disassembly and rebuild  (Read 107675 times)

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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #200 on: January 18, 2016, 02:58:37 PM »
Yeh, got the little 915 Stage III going New Years eve @ 11:30.
I shot a video, I'll try again. Yes, the sound is motivating! Bill
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Offline BPellerine

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Re: Cobra motor disassembly and rebuild
« Reply #201 on: January 18, 2016, 03:03:08 PM »
Yeh, got the little 915 Stage III going New Years eve @ 11:30.
I shot a video, I'll try again. Yes, the sound is motivating! Bill
the little 915?now you just rubbing it in!hahabillp
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #202 on: January 18, 2016, 06:24:09 PM »
Well, this is enough to get any old school performance enthusiast happy...made my day!!!
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Offline PeWe

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Re: Cobra motor disassembly and rebuild
« Reply #203 on: January 21, 2016, 03:37:01 AM »
and the cam is....?  RC315?
If it is a 315... measured IN/EX open/close at 0.04"  and total lift?
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #204 on: January 21, 2016, 04:29:57 AM »
327 PeWe, good looking one, Bill
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Offline gschuld

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Re: Cobra motor disassembly and rebuild
« Reply #205 on: January 21, 2016, 04:30:18 AM »
I think it says 327.   Good deal Billy.  How many 327s you got down there?  Must be a record collection at this point...

George

Offline PeWe

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Re: Cobra motor disassembly and rebuild
« Reply #206 on: January 21, 2016, 06:09:04 AM »
OK 327...racing only.
I'm curious about measured 315 data. If overlap is not too much I'll try it on the street if I can get one.
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Updates of the CB750 K6 -1976
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #207 on: January 21, 2016, 09:33:03 AM »
It'll work on the street....we build a few with 315's back in the day. If you are performance oriented. 295 next choice, hell the 327 can be ridden by knowledgeable riders on the street.
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Offline 754

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Re: Cobra motor disassembly and rebuild
« Reply #208 on: January 21, 2016, 10:16:16 AM »
315 was great on the street..fun..
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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #209 on: January 21, 2016, 11:41:48 AM »
It'll work on the street....we build a few with 315's back in the day. If you are performance oriented. 295 next choice, hell the 327 can be ridden by knowledgeable riders on the street.

Personally speaking, some of us have a hard time with the 327 on the dragstrip.

Offline gschuld

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Re: Cobra motor disassembly and rebuild
« Reply #210 on: January 21, 2016, 01:32:18 PM »
It'll work on the street....we build a few with 315's back in the day. If you are performance oriented. 295 next choice, hell the 327 can be ridden by knowledgeable riders on the street.

Personally speaking, some of us have a hard time with the 327 on the dragstrip.


 :o.           ;D

George

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #211 on: January 21, 2016, 02:48:59 PM »
It'll work on the street....we build a few with 315's back in the day. If you are performance oriented. 295 next choice, hell the 327 can be ridden by knowledgeable riders on the street.

Personally speaking, some of us have a hard time with the 327 on the dragstrip.
  Yeh right!  You especially handle it much better than most!
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #212 on: January 22, 2016, 01:20:53 PM »
If you don't feed it right, it won't eat.

Offline NitroHunter

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Re: Cobra motor disassembly and rebuild
« Reply #213 on: January 22, 2016, 02:26:13 PM »
315 was great on the street..fun..
+100 I loved mine too.
It was my experience the bigger cams really come to life with a higher CR piston, since the late closing intake valve doesn't allow the cylinder to build much pressure. Bigger bores with bigger domes cured that issue.  ;D
Lots of cylinder pressure makes them lots of fun. 
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #214 on: January 22, 2016, 05:35:36 PM »
Yah, going for all the cp I think dem 24 volts will turn!  Bill
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #215 on: February 01, 2016, 07:14:50 PM »
Going to need dem 24volts!! ;D ;D,Bill
« Last Edit: February 01, 2016, 08:14:52 PM by Bill/BentON Racing »
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #216 on: February 01, 2016, 08:27:23 PM »
Nice parts you have there Bill. I'm anxious to see the numbers you'll put up on the scoreboard. After all this hard work you deserve to get great results. I'm behind you all the way. Time to really turn this scooter into a full tilt dragbike and show the world that the SOHC's aren't dead yet.

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #217 on: February 01, 2016, 11:07:57 PM »
Frank,  thanks. Now got to put the puzzle together! Lol. ;D,Bill
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #218 on: February 18, 2016, 08:56:02 PM »
Another piece of the puzzle arrived today! ;D, Bill
BentON Racing Website
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #219 on: February 18, 2016, 09:18:37 PM »
Another piece of the puzzle arrived today! ;D, Bill

Heck Bill, you must own every RC block ever produced. Looking good!!

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #220 on: February 18, 2016, 10:30:30 PM »
Frank, I thought it was!!! Just shoot my ass! Me and RC blocks!!!!Bill  Bored, honed, fresh stainless o rings, just damn!
« Last Edit: February 18, 2016, 10:32:36 PM by Bill/BentON Racing »
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
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Offline calj737

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Re: Cobra motor disassembly and rebuild
« Reply #221 on: February 19, 2016, 05:57:38 AM »
Thats an interesting hairline seam across the front of those... Looks like an old crack that was repaired? Too regular to be casting flash  ???
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Offline dragracer

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Re: Cobra motor disassembly and rebuild
« Reply #222 on: February 19, 2016, 06:13:59 AM »
Thats an interesting hairline seam across the front of those... Looks like an old crack that was repaired? Too regular to be casting flash  ???
[/quot
Thats an interesting hairline seam across the front of those... Looks like an old crack that was repaired? Too regular to be casting flash  ???

Exactly what I was thinking but not so sure its a repair???

Offline Bill/BentON Racing

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Re: Cobra motor disassembly and rebuild
« Reply #223 on: February 19, 2016, 10:06:01 AM »
It's a crack for sure, not been repaired that I can tell,  Bill
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Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
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Offline madmtnmotors

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Re: Cobra motor disassembly and rebuild
« Reply #224 on: February 19, 2016, 10:30:20 AM »
It's a crack for sure, not been repaired that I can tell,  Bill

Is it still under warranty?   ;)
TAMTF...


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