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What is the difference between the TC88 & TC88B? And are the differences anything I should be concerened about?
 

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Road Hawg
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The 88B is the counter-balanced engine that the softalis have. It has wieights at the bottom of the engine, driven by yet another chain, that reduces the vibration of the engine. Now, I have been riding a rubber mount for years, but I rode a fat boy with an 88B engine about 2 years ago. It was a rental, so it had the stock exhaust- very quiet. No lie, I had to blip the throttle sometimes at a stop light to make sure the engine was still running. It was that smooth.

That said, I am leery of the MOCO putting another chain in an engine. I will switch to gear cams as soon as possible after I get my new bike this week.
 

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If you had intentions of building a high rpm engine, I would suggest the A (unbalanced engine). Other than that, get to a dealeer that will allow you to test drive both models and make a decision based on that.
 

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Hellbound Train
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The ballancers have been used in bikes up to 7,000rpm, so even with the rev limit punched up to 6,200, you are fine. Most builds fall off over that anyhow. I guess if you were building an all out drag racer, the ballancers would be an issue. But for a street racer it's not.
 

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remove balancers?

Always wondered about that. How about putting an A flywheel in a B motor? does it fit? are they balanced the same?
 

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A vs B- Downshifting

if you're one of those people (like me) who likes to match RPMs after you downshift by blipping the throttle, the B motor may not be for you. It is possible to 'overspeed' the balancers by inappropriate and aggressive downshifting.
 

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Wizwill said:
if you're one of those people (like me) who likes to match RPMs after you downshift by blipping the throttle, the B motor may not be for you. It is possible to 'overspeed' the balancers by inappropriate and aggressive downshifting.
What do you mean by 'overspeed'?
Fred
 

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Arrogant Bastard
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fredcrn said:
What do you mean by 'overspeed'?
Fred
He means he's not paying attention to what his bike is saying to him and downshifts too soon which over-revs the engine when he releases the clutch lever. Not a problem if you don't downshift to a lower gear at like 5k rpm.

Joe
 

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88 -v- 88B

I've owned both. I'm an OFG (old fat guy) so high power isn't my goal. The balanced motor is WAY smoother than the 88TC was in my '01 Dyna. But, in the B you are using chains to move weights on shafts so the laws of physics dictate some loss of hp to the crank and rear wheel. Enough to make a big difference? Probably not in stock bikes according to the dyno charts I've seen published.

Durability? Most 4 cyl cars have had chain driven balance shafts for years now w/o any apparent problems. But the chains driving the balance shafts aren't too accessible and aren't too sturdy looking in the bottom of the 88B. Yet, they've been running since the 2000 model year and haven't heard of the types of problems that early TC's had with cam drive and bearings.

I went smooth with a Fat Boy (and fuel injection). Ask yourself--do I like the vibration traditional to HD or the smooth version better? Or cheat and get a V Rod which has rubber mounting like a Dyna and balance shafts.
 

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I have an RK, but my previous bike was a Fat Boy. The B motor is smooth, until you hit 70, then it vibrates right through the handlebars.
 
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