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Discussion Starter #1
Recently I just had s&s gear drive cams installed in my '06 Dyna street bob 88 cu. in. My issue is that when I slow down the motor bogs down and acceleration is horrible(sputters like it is going to die). Currently I have screaming eagle II pipes. No sure what is the issue or how to fix it. Any help out there.
 

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What was done to adjust the fuel and ignition timing to account for the new cams?
 

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Discussion Starter #5
I believe nothing was done to the timing. Not to sure what exactly I need to do for that. What do suggest?
 

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On an EFI bike, you'll need either a piggy-back tuner like a Power Commander or similar or you'll need a SERT (Screamin' Eagle Race Tuner). The SERT will re-flash your ECM. It's the only way to get additional fuel in.

Either way, you need someone who knows what they are doing to set up everything.

I have to ask, what sort of mechanic would install a set of cams and not consider this?

Which cams were installed? There are many S&S gear drive cams. They all have different valve lift and duration.
 

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Discussion Starter #7
The cams that were install were S&S 510G camshaft kit. was told that these cams were just a direct bolt in designed for stock heads. I did have Harley Davidson run a diagnosis because of engine light coming on and off. The result was front and rear cylinders no combustion. which is weird since the bike runs. still scratching my head on this problem...
 

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When you say "bogs down when you slow" I think of a jake brake on a road tractor. Those use exhaust back pressure to slow the motor and thus slow the truck.

If that is what you are experiencing it sounds like the exhaust valves are not opening at the right time or not enough at all.

Maybe the cams got off a tooth when they were pressed in the plate. I believe there is also an index mark for the crank gear and the outer cam gear.


Did they cut the push rods out and go back in with the collapsible adjustables or did they pull the rocker covers and go back with the stock rods?


Sent from Motorcycle.com App
 

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Discussion Starter #9
Well as far as I am a wear the timing was done correctly. I was told that even if you off by a tooth the bike wouldn't even start. The stock push rods were used.

The way the bike is reacting is I am having to constantly double clutching to take off from dead stop. Also when riding in any gear when letting off the throttle and getting back on it the motor bogs and sputters. Then I have to double clutch to get the Rpm's back up to get going.

I was told now to try replacing my spark plug wires, which make no since to me because the bike runs. But I will give it a shot since it is a cheap fix if that is the problem.

The other solution I have been told is to take it to a dyno and have the ECM remapped.
Which in my case is a every expense process. So still attempting to figure out this problem.
 

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A re-map is probably in order since you've already changed the pipes and now the cams.

Bite the bullet and get it tuned! Allot of people spend big money on cams and pipes but
they seem reluctant to spend some money/time on the dyno. Trust me, this is money
well spent! Especially after you've already done some really nice mods.

Consider some headwork too! A little porting and a compression bump will really wake
that thing up! (BigTime)
 

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The 510 is a bolt in for that it .. Bolt in= means nothing more than no other mods needed to install. That 510 in a 88 incher is a dog. A set of Andrews 21 or 26 would have been a much better set up by far. Did the shop talk to you about tuning the engine for the new cams? if not it may be time to find another shop. As there is no way the stock map is going to even be in the ball park with a set of 510 cams in a 88 incher. I am sure it does not run well. Many tuning shops in California find one and explain what was done and what the bike is doing. If you give a better location I can help you with a tuner that is close to that area that I know. Good luck
 

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A re-map is probably in order since you've already changed the pipes and now the cams.

Bite the bullet and get it tuned! Allot of people spend big money on cams and pipes but
they seem reluctant to spend some money/time on the dyno. Trust me, this is money
well spent! Especially after you've already done some really nice mods.

Consider some headwork too! A little porting and a compression bump will really wake
that thing up! (BigTime)
+1 tune it!

New to the bike world but not to the modding world. Any time you are changing internal specs you HAVE to re-tune. Heck a tune will do you good without mods in some cases.
 

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Sure sounds like the cam timing is off. I'd make the mechanic who did the work check the cm timing.
I bet on one tooth off.
 
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