Author Topic: Project "Evolution" 78' CB750K... the morphing continues... (Read 76561 times)

MRieck · « **Reply #150 on:** March 12, 2016, 05:27:11 AM »

Quote from: madmtnmotors on March 12, 2016, 04:20:19 AM

Quote from: calj737 on March 12, 2016, 03:44:51 AM
Wilbur, just double-check the valve-piston clearance.

Well, I did clay the pistons (more for practice than anything else) with the Webcam 41. Now that everything is bolted up (and re-torqued), how do I check it now? Fish a piece of solder through the spark plug hole? Order another head gasket and rip the head back off? If I had to order a head gasket and rip the head off then I'd just as soon order another Webcam 41 and work on something else while I wait...

You can pry down on the rocker arm ( with a dial guage on the retainer) Wilber. You check @ 10degress BTDC and ATDC. I'd advise using a crappy cam cover as it can screw up the tappet cover threads. I use a long, square shaft screwdriver...it does roll off the rocker arm when prying down.

madmtnmotors · « **Reply #151 on:** March 12, 2016, 05:47:52 AM »

Quote from: MRieck on March 12, 2016, 05:27:11 AM

Quote from: madmtnmotors on March 12, 2016, 04:20:19 AM
Quote from: calj737 on March 12, 2016, 03:44:51 AM
Wilbur, just double-check the valve-piston clearance.

Well, I did clay the pistons (more for practice than anything else) with the Webcam 41. Now that everything is bolted up (and re-torqued), how do I check it now? Fish a piece of solder through the spark plug hole? Order another head gasket and rip the head back off? If I had to order a head gasket and rip the head off then I'd just as soon order another Webcam 41 and work on something else while I wait...
You can pry down on the rocker arm ( with a dial guage on the retainer) Wilber. You check @ 10degress BTDC and ATDC. I'd advise using a crappy cam cover as it can screw up the tappet cover threads. I use a long, square shaft screwdriver...it does roll off the rocker arm when prying down.

Now that I can do! As long as I don't have to take the top end back apart again...

madmtnmotors · « **Reply #152 on:** March 12, 2016, 09:20:40 AM »

Well, thanks for the reality check guys. I actually found another thread from garage-guy-chris where he had already fitted and checked a KHD cam against CI's pistons and was too tight.

As for my measurements, both the intake and exhaust valves come within about .012" within 10 degrees btc and atc (checked every 2 degrees).

Looks like the duration is the deal breaker here. i.e. opens too soon (intake) and closes too late (exhaust)

Soooo.... looks like three options:

>Get another Webcam 41 (either warranty replaced or source another)
>Use a stock K8
>Use a stock F2

tick, tock....

I will probably just get on the other bike and ride for the rest of the afternoon.

Davez134 · « **Reply #153 on:** March 12, 2016, 06:04:18 PM »

Have you tried contacting webcam for an answer yet? In my experience, their customer service has been good. Especially since you have these pictures. Did you buy direct from them, or a distributor? (I looked through the thread and didn't see)

madmtnmotors · « **Reply #154 on:** March 12, 2016, 07:20:26 PM »

Quote from: Davez134 on March 12, 2016, 06:04:18 PM

Have you tried contacting webcam for an answer yet? In my experience, their customer service has been good. Especially since you have these pictures. Did you buy direct from them, or a distributor? (I looked through the thread and didn't see)

Waiting on a response from the distributor before I weigh in on their customer service...

I have also reached out to Jim French, our resident microwelder, about a potential repair if the warranty efforts fall through.

Retro Rocket · « **Reply #155 on:** March 12, 2016, 09:41:29 PM »

Quote from: madmtnmotors on March 12, 2016, 07:20:26 PM

Quote from: Davez134 on March 12, 2016, 06:04:18 PM
Have you tried contacting webcam for an answer yet? In my experience, their customer service has been good. Especially since you have these pictures. Did you buy direct from them, or a distributor? (I looked through the thread and didn't see)

Waiting on a response from the distributor before I weigh in on their customer service...

I have also reached out to Jim French, our resident microwelder, about a potential repair if the warranty efforts fall through.

Don't let the "warranty" fall through mate, thats clearly drilled off center, I've looked at a lot of cams since you posted that pic and NONE were like that Webcam you have...

madmtnmotors · « **Reply #156 on:** March 13, 2016, 07:20:40 AM »

Quote from: calj737 on March 13, 2016, 07:15:10 AM

Bummer, Wilbur. But at least you found out before the cam poked a hole in those slugs.

Oh yeah, I'm all for getting it right. As much as I'd like to use the hotter cam, I'm not going to tear it down to cut the pistons at this point. Leaning towards the F2 cam.

madmtnmotors · « **Reply #157 on:** March 22, 2016, 05:28:09 AM »

Definitely moving forward now! Except for the part where I knocked the headlight off the bench and broke it...

Opted for the F2 cam since the Webcam 41 is on its way back to where it came from and the "D" grind will need flycut pistons (next build). Should have it running by this weekend, ready to start the 500 mile break in.

>Cylinders and head painted to match the cases. Engine is in the frame!
>Increased the main jets from 110 to 125 since we're now rockin' 836cc with a mildly ported head.
>Dyna coils along with Dyna S installed and static timed
>Added a couple of relays to take the load off of the ignition switch, not sure how many more wires I can fit into the headlight bucket...
>Added a "trigger" wire from the coil for a shift light

Left to do:
>Install new custom rear fender
>Finish tightening bolts

After the 500 mile break in:
>Install 1/4 turn throttle
>Lower the forks and shorten the shocks
>Fit drag pipes
>Drag handle bars? (Time permitting)
>Add "go fast" decals
>Head for the local track for test and tune

Work on the bike got trumped this weekend. Got to see the Outlaws perform Friday night, which would have been pretty cool all by themselves, but they were the warm up band for George Thorogood! Then turned around Saturday morning and drove to Gainesville for the Gator Nationals! Got to meet "Mr. Drag Racing" himself:

Courtney kept hitting on me, but I had to explain to her that I was happily married. She was disappointed, but didn't take it too hard, since right after this photo was taken she went out and ripped off a number 2 qualifying run at 325mph in 3.69 seconds!

Stev-o · « **Reply #158 on:** March 22, 2016, 05:37:11 AM »

That's awesome, Wilbur, I really like John Force. Courtney, Ashley and Britney too, three hot daughters!

madmtnmotors · « **Reply #159 on:** March 22, 2016, 05:42:36 AM »

Yeah, he definitely got it right. Brittany won the event in top fuel (her first event win).

madmtnmotors · « **Reply #160 on:** March 27, 2016, 05:27:51 PM »

We have a runner! Fired right up, short warm up then settled into a 950rpm idle. Synced the carbs, dynamic check of timing, went for a ride...

Then spent all weekend trying to figure out why it would pull hard up to 5500 rpm then fall flat on its face. Cranking the throttle to wide open would bring upon sputtering and surging, but below 5000 rpm it would run perfect. Turns out the increase to 836cc did not require such a drastic increase in main jets from 110 to 125. Reverting back to 110 mains settled everything down and now runs more like it should all the way to 8500 rpm. I'll put down as many break in miles as I can this week and then off to the local track for test-n-tune next weekend!

Stev-o · « **Reply #161 on:** March 27, 2016, 06:14:33 PM »

Good news!

Retro Rocket · « **Reply #162 on:** March 27, 2016, 06:16:47 PM »

Quote from: Stev-o on March 27, 2016, 06:14:33 PM

Good news!

+1

Desert-SOHC · « **Reply #163 on:** March 27, 2016, 06:30:26 PM »

Great!

SOHC4 Cafe Racer Fan · « **Reply #164 on:** March 27, 2016, 08:21:51 PM »

Excellent!

scottly · « **Reply #165 on:** March 27, 2016, 08:33:32 PM »

Quote from: madmtnmotors on March 27, 2016, 05:27:51 PM

Turns out the increase to 836cc did not require such a drastic increase in main jets from 110 to 125. Reverting back to 110 mains settled everything down and now runs more like it should all the way to 8500 rpm.

Yup, an increase in air-flow generates more "pull" on the main jets. That's how carburetors work...

madmtnmotors · « **Reply #166 on:** April 19, 2016, 10:04:22 AM »

Quote from: madmtnmotors on March 12, 2016, 07:20:26 PM

Quote from: Davez134 on March 12, 2016, 06:04:18 PM
Have you tried contacting webcam for an answer yet? In my experience, their customer service has been good. Especially since you have these pictures. Did you buy direct from them, or a distributor? (I looked through the thread and didn't see)

Waiting on a response from the distributor before I weigh in on their customer service...

I have also reached out to Jim French, our resident microwelder, about a potential repair if the warranty efforts fall through.

Update:

Ken at Cycle X has convinced WebCam to replace the defective CX-1 cam. Woo-Hoo! Thanks Ken! I figured it would be covered due to the improperly drilled flange. Should ship out any day now.

I will reach out to any cam supplier in the future, prior to installing a cam that has any visible defects, just to be on the safe side.

Davez134 · « **Reply #167 on:** April 19, 2016, 11:40:43 AM »

Awesome! Glad to hear they did the right thing.

SOHC4 Cafe Racer Fan · « **Reply #168 on:** April 19, 2016, 01:25:24 PM »

Great news. I like it when manufacturers stand behind their products - especially specialty items like performance engine parts.

Desert-SOHC · « **Reply #169 on:** April 19, 2016, 05:12:56 PM »

that's awesome!

BPellerine · « **Reply #170 on:** April 19, 2016, 06:18:49 PM »

a little harder to keep the front end down with the new cam?haha bill

Restoration Fan · « **Reply #171 on:** April 20, 2016, 04:58:52 AM »

Good news but don't get caught up in the 'go faster' mentality quite yet. Keep doing what you're doing at getting good at running consistent times to win Street ET.

It's easy to try to shoot for 11's then 10's then 9's etc on these bikes but Frank keeps proving that consistency wins these races, not speed. And as we already know, the 78's are the fastest already anyways!

Congrats on a great job down in Valdosta, Wilbur! Keep showing these boys what a SOHC bike can do.

RandyBMC · « **Reply #172 on:** April 20, 2016, 06:09:10 PM »

That must be a great feeling hearing it run! I can't even imagine what it would be like to ride it!

Congrats

madmtnmotors · « **Reply #173 on:** October 22, 2016, 01:21:47 PM »

Update: Front end has been lowered and preloaded by 1-1/2". At rest there is no compression of the fork springs now, so there is no extension of the forks upon launch off the starting line. This has helped reduce the wheelies. I still managed to pull the front wheel a couple of times at "The Rock" last month, but they were more subdued. The flamed fuel tank that was caved in on the way to Memphis (broken tie down strap... dammit!) has been replaced with a straight tank sporting original paint. Flat drag handlebars along with a 1/4 turn throttle round out the bulk of the mods to date.

The only other mod so far has been the addition of a rev limiter that I just finished up yesterday. A quick 30 mile "shakedown" today to "get-er-dialed" and I've got the rev limiter coming on around 9500 right now. Special shout out to POPS for cutting me a great deal on the Dyna 200DRL! I would have installed it sooner, but I lost the friggin box that I put it in and spent the last three months looking for it!

The only thing left to do for the near future is the addition of a shift light. Picts to follow... stay tuned!

Restoration Fan · « **Reply #174 on:** October 26, 2016, 07:47:35 PM »

Good luck with it in Valdosta, Wilbur!

Ron

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Author Topic: Project "Evolution" 78' CB750K... the morphing continues... (Read 76561 times)