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Discussion Starter · #1 ·
Polishing the covers over the past few days has my Bonneville nearly complete. It's not nearly the custom that some folks here have, but it's all mine. I tried to maintain a mostly stock appearance, do a few subtle modifications for apearance and performance.

Engine:
-Wiseco 90mm HC pistons
-BC Street Cams
-FCR39s
-Uni filters
-Procom ignitor
-Heavy clutch springs
-Bubs full system

Other:
-Superbars
-Football grips
-Polished engine and sprocket covers
-Fork Gaitors
-Shark fin shaved
-Reflectors gone
-Tach with homebrew bracket
-AI removed
-Long seat bolts

Still have to do:
-Tighten up the valves
-Bar end mirrors

Still thinking about:
-Modifying and ceramic coating stock headers to work with Bubs (want to see the effects of crossover tube)
-Polishing cam cover

Performance wise, I am pretty happy. The cams/ carbs/ and pistons are a dynamite combination. Took me a little while to get the carbs dialed in, but right now they are very close. Still need to get back to the dyno for the fine tuning. On the last trip I was making about 56ft-lbs in the mid-range, but falling off up top as it got wicked rich. I've since changed the filters, dialed in the main, and changed to needles to bring them back into useful adjustment range. That last run was with K&Ns also, and I believe my new 6" Unis allow a little more air in at high revs.

A few pictures:






And one with the Mrs posing:


Not sure how to post a video, but here is a link....

http://www.youtube.com/watch?v=Lj7Nbs7SLOo
 

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Looks good! I like your polished covers!!
 

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Awesome dledinger.
A couple of questions please...
How many miles were on it when you installed the HC pistons? Can you explain what you did to deglaze the cylinders?...did you perform a post build leak down or compression check? Many of us wonder what kind of piston/ring seal can be achieved by putting the Weisco forged HC pistons in used Nikasil bores. I know you are sorting it, but how does it pull compared to stock?...sounds strong in the video :)
Congrats,
George
 

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Discussion Starter · #4 ·
Sure,

I suffed them with scotch brite, washed in soapy water, and checked with a bore gauge.

My bores had 4K miles on them, and were like new: round, uniform, and with complete honing marks.

I have not done a leak down test or a compression check....as I am just hitting 500 miles on the new pistons. The rings should be well sealed by now, and I hope to here in the near future.

It pulls great compared to stock. No comparison...just roll-on, and go.
 

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That's a lot of work gone into it, and a damn fine looking bike - well done sir!
 

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Is there any particular technique you used with the scotchbrite pads?...did you use the green pads?...scuff in the same direction as the X-hatching?..or up and down?
Thanks,
George
 

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Discussion Starter · #7 ·
I used green and went with the cross hatching, but I dont think it matters much. The bore lining is so hard that the scotch brite doesn't touch it. All you are removing is the glaze.
 

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Quite right...even fine sandpaper won't take down Nikasil...only diamonds...how the hone pattern is put in after the factory bore is sized and plating complete. So honing Nikasil short of using a diamond hone is really a misnomer...not honing at all and in fact conventional stone hones in an effort to re-hone nikasil are said to only lay over the Nikasil X-hatch and make it worse.

I look forward to your dyno pulls as I am curious about your piston and cam combo as no doubt others are...more aggessive cams like compression to preserve torque.
Well done and thanks for sharing it with us,
George
 

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The bike looks great - and sounds great too; I watched the film clip twice. Those Bub silencers look the business indeed.
Oh, what is a "shark fin". You say you shaved yours. Mine might need a shave too, if I could find it.
 

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nice bike.

Not to diss your bike, but you're losing some serious hp with those bubs compared to some other options like stock bonnie or thrux (better) headers with Preds/Dominators or a D&D 2-1 system. I used to run bubs and I loved 'em, and wouldn't believe the claims until I tried it for myself and got my bike on the dyno.
 

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Your video

dledinger: Completely off topic, but I couldn't help but notice...

Your profile says you're in NC, you're wearing funny clothes in your profile picture, and that video looks suspiciously like the road out to Courtyard Bay... haha! Am I close?

More to the point, your scoot looks killer!

Cheers,
-Lee
 

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Discussion Starter · #15 ·
George,

Just an update. You peaked my interest last night and motivated me to get out and tinker some more...so I pulled out my pressure gauge.

I was pleased to find that I am reaching 195 PSI in each cylinder. I get around 90 on the first pump, then it is maxed out at 195 by the fourth or fifth.

Unfortunately, I do not have the setup to do leakdown testing here at home.

Think the rings are sealed?

Awesome dledinger.
A couple of questions please...
Can you explain what you did to deglaze the cylinders?...did you perform a post build leak down or compression check? Many of us wonder what kind of piston/ring seal can be achieved by putting the Weisco forged HC pistons in used Nikasil bores.
 

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George,

Just an update. You peaked my interest last night and motivated me to get out and tinker some more...so I pulled out my pressure gauge.

I was pleased to find that I am reaching 195 PSI in each cylinder. I get around 90 on the first pump, then it is maxed out at 195 by the fourth or fifth.

Unfortunately, I do not have the setup to do leakdown testing here at home.

Think the rings are sealed?
195/14.7=13.27:1 CR
Yup. :)
Congrats and again nice job on the bike,
George
 

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I was pleased to find that I am reaching 195 PSI in each cylinder.
COMPRESSION TESTS

You can expect the cranking pressure in psi for a road engine with a standard cam to be about 17 to 20 times the value of the compression ratio. So our engine with a CR of 10:1 should generate between 170 and 200 psi. The better the condition of the engine the closer the figure will be towards the top end of this range. If the engine has been modified by fitting a different cam then you need to make some allowances. Fast road cams will reduce the expected figure by 10 psi or so.
So your 10.5:1 engine with high overlap cams should be between 170 and 200psi aprox. In that case I'd say 195psi is very good.
 

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Discussion Starter · #19 ·
Sweat....LOL!

Actually, not a problem at all, and good to know.

Thank you!

Although, I do find it rather amusing that you correct my grammar but neglect proper capitalization in your own post. Hell, you even had a sentence fragment in that post. ;)
 
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