Author Topic: Performance camshafts and 750 aftermarket guide seals  (Read 5258 times)

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Offline MRieck

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Performance camshafts and 750 aftermarket guide seals
« on: April 06, 2013, 01:07:30 pm »
 I was looking at several different aftermarket seals (green and black ones) last night and noted that both were .040 to .048 taller than OEM seals. There really isn't much retainer to seal clearance to begin with on the 750's....adding a high lift will tap the seal and distort the sealing lip. You will burn oil all the time. Something to keep in mind and another reason why I like OEM seals on the 750.
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Offline brandEn

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #1 on: April 06, 2013, 02:26:42 pm »
Hmm, that's why I sent you a set of green and a set of black. Wasn't sure which was better. Looks like neither! haha

Offline Retro Rocket

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #2 on: April 06, 2013, 04:16:12 pm »
I was looking at several different aftermarket seals (green and black ones) last night and noted that both were .040 to .048 taller than OEM seals. There really isn't much retainer to seal clearance to begin with on the 750's....adding a high lift will tap the seal and distort the sealing lip. You will burn oil all the time. Something to keep in mind and another reason why I like OEM seals on the 750.

Are they locally manufactured seals Mike, i was just wondering if they would appreciate your feedback. Are the aftermarket seals made of better material..?

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Offline MCRider

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #3 on: April 06, 2013, 04:27:22 pm »
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #4 on: April 06, 2013, 05:39:25 pm »
I got my green ones off eBay. Supposedly some trick material. Maybe part of my smoking problem?

http://www.ebay.com/itm/HONDA-SOHC-CB750-CB-750-VALVE-STEM-SEALS-VITON-/300468201164?pt=Motorcycles_Parts_Accessories&hash=item45f54ce6cc&vxp=mtr
Ron....your problem was more collective. And it will be righted. ;D Took the sleeves out of the donor block today. New sleeves in a week....it's moving.
 This project will be very satisfying for me. A long time 750 enthusiast looking for a legacy machine. You will get it and more. I only wish I could do more of these with the attitude Ron has afforded me.
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Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #5 on: April 06, 2013, 05:43:20 pm »
I was looking at several different aftermarket seals (green and black ones) last night and noted that both were .040 to .048 taller than OEM seals. There really isn't much retainer to seal clearance to begin with on the 750's....adding a high lift will tap the seal and distort the sealing lip. You will burn oil all the time. Something to keep in mind and another reason why I like OEM seals on the 750.

Are they locally manufactured seals Mike, i was just wondering if they would appreciate your feedback. Are the aftermarket seals made of better material..?
Mick
OEM are brown in color....I have never seen that color before with the aftermarket viton seals. The OEM look very good....I can see using aftermarket for the 550's ( red Kibblewhite's with the spring around the seal lip) but in my mind the OEM are the best for the 750. Just an observation backed up by measurements.
« Last Edit: April 06, 2013, 05:50:29 pm by MRieck »
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Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #6 on: April 06, 2013, 05:53:50 pm »
Hmm, that's why I sent you a set of green and a set of black. Wasn't sure which was better. Looks like neither! haha
Correct. Your $hit is ready to ship......no way I'll take a chance on that stuff. I can't wait to see how that engine runs. ;))That's how I got the green ones BTW. ;D ;D ;D Maybe this thread should be transferred to the archives?
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Offline MCRider

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #7 on: April 06, 2013, 06:53:59 pm »
I got my green ones off eBay. Supposedly some trick material. Maybe part of my smoking problem?

http://www.ebay.com/itm/HONDA-SOHC-CB750-CB-750-VALVE-STEM-SEALS-VITON-/300468201164?pt=Motorcycles_Parts_Accessories&hash=item45f54ce6cc&vxp=mtr
Ron....your problem was more collective. And it will be righted. ;D Took the sleeves out of the donor block today. New sleeves in a week....it's moving.
 This project will be very satisfying for me. A long time 750 enthusiast looking for a legacy machine. You will get it and more. I only wish I could do more of these with the attitude Ron has afforded me.
Thanks, I kinda figured it was a little of several things. At least it wasn't an assembly problem (I think?) At least I didn't break a ring.

Carry on! I'm excited!  I'm installing new APE studs tomorrow, after removing the base gasket.   :D
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #8 on: April 06, 2013, 07:34:49 pm »
Ron, why are you removing the base gasket? Broken? If not leave it in place and reuse or Mike can hook you up with a modern coated steel one. Won't tear like the original style.

As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #9 on: April 06, 2013, 07:46:51 pm »
I got my green ones off eBay. Supposedly some trick material. Maybe part of my smoking problem?

http://www.ebay.com/itm/HONDA-SOHC-CB750-CB-750-VALVE-STEM-SEALS-VITON-/300468201164?pt=Motorcycles_Parts_Accessories&hash=item45f54ce6cc&vxp=mtr
Ron....your problem was more collective. And it will be righted. ;D Took the sleeves out of the donor block today. New sleeves in a week....it's moving.
 This project will be very satisfying for me. A long time 750 enthusiast looking for a legacy machine. You will get it and more. I only wish I could do more of these with the attitude Ron has afforded me.
Thanks, I kinda figured it was a little of several things. At least it wasn't an assembly problem (I think?) At least I didn't break a ring.

Carry on! I'm excited!  I'm installing new APE studs tomorrow, after removing the base gasket.   :D
No assembly problem Ron....you did that correctly. I'm more worried about that Waller guy and his trick head. ;) ;) ;) ;) ;) :D
« Last Edit: April 06, 2013, 07:48:37 pm by MRieck »
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Offline bwaller

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #10 on: April 06, 2013, 08:12:09 pm »
I got my green ones off eBay. Supposedly some trick material. Maybe part of my smoking problem?

http://www.ebay.com/itm/HONDA-SOHC-CB750-CB-750-VALVE-STEM-SEALS-VITON-/300468201164?pt=Motorcycles_Parts_Accessories&hash=item45f54ce6cc&vxp=mtr
Ron....your problem was more collective. And it will be righted. ;D Took the sleeves out of the donor block today. New sleeves in a week....it's moving.
 This project will be very satisfying for me. A long time 750 enthusiast looking for a legacy machine. You will get it and more. I only wish I could do more of these with the attitude Ron has afforded me.
Thanks, I kinda figured it was a little of several things. At least it wasn't an assembly problem (I think?) At least I didn't break a ring.

Carry on! I'm excited!  I'm installing new APE studs tomorrow, after removing the base gasket.   :D
No assembly problem Ron....you did that correctly. I'm more worried about that Waller guy and his trick head. ;) ;) ;) ;) ;) :D

Don't worry sire, I thinks it's on right way round.  I made notes when it came apart.  ;)

Offline brandEn

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #11 on: April 06, 2013, 08:50:49 pm »
Hmm, that's why I sent you a set of green and a set of black. Wasn't sure which was better. Looks like neither! haha
Correct. Your $hit is ready to ship......no way I'll take a chance on that stuff. I can't wait to see how that engine runs. ;))That's how I got the green ones BTW. ;D ;D ;D Maybe this thread should be transferred to the archives?

That's a very satisfying thing to hear. Sweet.

Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #12 on: April 06, 2013, 08:57:17 pm »
I got my green ones off eBay. Supposedly some trick material. Maybe part of my smoking problem?

http://www.ebay.com/itm/HONDA-SOHC-CB750-CB-750-VALVE-STEM-SEALS-VITON-/300468201164?pt=Motorcycles_Parts_Accessories&hash=item45f54ce6cc&vxp=mtr
Ron....your problem was more collective. And it will be righted. ;D Took the sleeves out of the donor block today. New sleeves in a week....it's moving.
 This project will be very satisfying for me. A long time 750 enthusiast looking for a legacy machine. You will get it and more. I only wish I could do more of these with the attitude Ron has afforded me.
Thanks, I kinda figured it was a little of several things. At least it wasn't an assembly problem (I think?) At least I didn't break a ring.

Carry on! I'm excited!  I'm installing new APE studs tomorrow, after removing the base gasket.   :D
No assembly problem Ron....you did that correctly. I'm more worried about that Waller guy and his trick head. ;) ;) ;) ;) ;) :D

Don't worry sire, I thinks it's on right way round.  I made notes when it came apart.  ;)
yeah.....your stuff is going to cause some problems.......with other people! ;) ;)
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Offline MCRider

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #13 on: April 07, 2013, 06:20:10 am »
Ron, why are you removing the base gasket? Broken? If not leave it in place and reuse or Mike can hook you up with a modern coated steel one. Won't tear like the original style.
No its actually in very good shape. I just put Gasgacinch on the case side so its stuck down. No selaer on the cyl side so they came off easy.  Think I should leave it?

Just didn't want to ba accused of shortcutting. I have a mls gasket from CycleX guaranteed for life.
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #14 on: April 07, 2013, 07:55:52 am »
Ron, why are you removing the base gasket? Broken? If not leave it in place and reuse or Mike can hook you up with a modern coated steel one. Won't tear like the original style.
No its actually in very good shape. I just put Gasgacinch on the case side so its stuck down. No selaer on the cyl side so they came off easy.  Think I should leave it?

Just didn't want to ba accused of shortcutting. I have a mls gasket from CycleX guaranteed for life.
That is the way to go. just need both surfaces to be smooth. The new cylinder bottom will be perfect no that the sleeves are out.
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Offline MCRider

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #15 on: April 07, 2013, 08:35:08 am »
Ron, why are you removing the base gasket? Broken? If not leave it in place and reuse or Mike can hook you up with a modern coated steel one. Won't tear like the original style.
No its actually in very good shape. I just put Gasgacinch on the case side so its stuck down. No selaer on the cyl side so they came off easy.  Think I should leave it?

Just didn't want to ba accused of shortcutting. I have a mls gasket from CycleX guaranteed for life.
That is the way to go. just need both surfaces to be smooth. The new cylinder bottom will be perfect no that the sleeves are out.
OK, gasket removal it is. With the studs out, it shouldn't be too hard. (famous last words)  :D
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #16 on: April 07, 2013, 10:51:38 am »
That's the one I referred to. By all means, use it. No coatings though.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline PeWe

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #17 on: April 08, 2013, 03:13:25 am »
- I need to check the sealing height/clearance when using a CycleX CX-7 cam?  :o
Similar to the Mega Cycle 125-75 but with 3 more degrees of duration.

I managed to assemble the crankcase halves yesterday so pistons, cylinder block and head are soon there for clearance check and timing. Another thing to check then.
Thank you very much for the good advice  :D
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Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #18 on: April 11, 2013, 07:45:32 am »
I also noticed several other differences betwen the aftermarket "black" and "green" seal. First off neither has the steel shoulder built into the upper part of the OEM seal. This shoulder provides stability and reduces distortion of the seal lip. Speaking of seal lips....the OEM seal has a very distinct lip....the other 2 do not. A big difference is the actual ID of the stem hole. The "black" seal hole is noticably larger than OEM. The "green" hole much, much smaller. ???
 I just did a head for Branden and he supplied a set of both the "black" and "green" seals. I did not put them in for all the reasons I have listed.
 I have not seen the Kibblewhite seals for the 750 though I will order a set to check them out. The Kibblewhite 550 seals are good IMO for all the reasons I have spoken about.
 I know it sounds kinds stupid to go over something as simple as a seal BUT if you have invested a lot of time and money in a project the last thing you want to happen is have it blow smoke.
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Offline Tintop

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #19 on: April 11, 2013, 01:17:20 pm »
Thanks for posting the info Mike.  Fits in with what I have to use on the sidecar motor.  The higher lift cam requires the use of shorter than stock seals.
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Offline MCRider

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #20 on: April 11, 2013, 04:08:32 pm »
I also noticed several other differences betwen the aftermarket "black" and "green" seal. First off neither has the steel shoulder built into the upper part of the OEM seal. This shoulder provides stability and reduces distortion of the seal lip. Speaking of seal lips....the OEM seal has a very distinct lip....the other 2 do not. A big difference is the actual ID of the stem hole. The "black" seal hole is noticably larger than OEM. The "green" hole much, much smaller. ???
 I just did a head for Branden and he supplied a set of both the "black" and "green" seals. I did not put them in for all the reasons I have listed.
 I have not seen the Kibblewhite seals for the 750 though I will order a set to check them out. The Kibblewhite 550 seals are good IMO for all the reasons I have spoken about.
 I know it sounds kinds stupid to go over something as simple as a seal BUT if you have invested a lot of time and money in a project the last thing you want to happen is have it blow smoke.

Really?   ;)
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline MRieck

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Re: Performance camshafts and 750 aftermarket guide seals
« Reply #21 on: April 12, 2013, 05:19:34 am »
I also noticed several other differences betwen the aftermarket "black" and "green" seal. First off neither has the steel shoulder built into the upper part of the OEM seal. This shoulder provides stability and reduces distortion of the seal lip. Speaking of seal lips....the OEM seal has a very distinct lip....the other 2 do not. A big difference is the actual ID of the stem hole. The "black" seal hole is noticably larger than OEM. The "green" hole much, much smaller. ???
 I just did a head for Branden and he supplied a set of both the "black" and "green" seals. I did not put them in for all the reasons I have listed.
 I have not seen the Kibblewhite seals for the 750 though I will order a set to check them out. The Kibblewhite 550 seals are good IMO for all the reasons I have spoken about.
 I know it sounds kinds stupid to go over something as simple as a seal BUT if you have invested a lot of time and money in a project the last thing you want to happen is have it blow smoke.

Really?   ;)
Unfortunately I think you would know better than anybody about that Ron. Nothing that cannot be fixed. ;)
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