RPM Question

FatBoyNoMore

I purchased a 1995 ST1100 about three weeks ago (LOVING' IT!) after selling my 1991 HD FatBoy. Most of the transition has been SO easy.

But one thing has been plaguing me is a growling/clattering noise when I roll on the throttle to accelerate from low RPM's, like 2-2.5k. The sound is like a diesel pickup accelerating quickly but from the transmission, not the engine.

I asked my mechanic about it today and he had researched a similar problem for a customer a few years ago. The answer came back from Honda that the rider needed to relearn how to ride the bike. Basically it's a normal noise coming from abnormal riding.

It turns out I am riding my V-4 like a big V-Twin and need to relearn how to operate at higher RPM's.

So my questions are --

1. where is the ST1100 happiest for performance and efficiency when cruising around town or highway?
​
3-4K? above 4K? above 5K?

2. I get that noise a lot when taking off from a dead stop. So, on the ST is it best to rev up to >3k and friction zone up to speed, or keep lower RPM and just roll on the throttle slower to avoid the growling clatter noise?

:bow1:Thank you for the anticipated wisdom from a great community!! :bow1:
 
The ST will idle along nicely at 2500 rpm in top (5th), but it wont accelerate very well here. Drop a cog or two and away it will go.

Performance acceleration, wait untill 6000 or so to change up. 7000 and its a rocket.

For pulling away from a stop, 1500 - 2000, and accelerate slightly as the clutch comes out, there may be a bit of chatter if the engine is cold (clutch skips a little). 3000 is a little bit much.

The bike loves to sit at 4000+ , and does it really well.

Cruising around town, 4th gear and 3 grand it will be quite happy, infact you may forget to change up as you leave the city limits. The engine is so quiet its easy to forget.

The 1100 is an easy bike to ride, but coming from a Harley it may take a little getting used to. Listen to the engine and transmition, and the bike will soon be telling you what it wants to do.

Oh, there is no need to stop for fuel every 60 miles (100Kilometers), you should be able to do 240 miles easily. :)
 
FatBoyNoMore said:
I asked my mechanic about it today and he had researched a similar problem for a customer a few years ago. The answer came back from Honda that the rider needed to relearn how to ride the bike. Basically it's a normal noise coming from abnormal riding.

It turns out I am riding my V-4 like a big V-Twin and need to relearn how to operate at higher RPM's.
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Yep, he's absolutely right. Most of tthe V-Twin designs you find in cruisers tend to peak and peter out early; your Fat Boy was no exception. The lack of torque at higher RPMs is the reason cruisers aren't famous for their 0-100 times.

Getting to know your 1100's torque curve is one of the best things you can do for your riding. Where your Fat Boy peaked out at 3,500 RPM, your ST is just coming off a small bump and getting warmed up for the climb to 6,500. If you haven't ventured above 4,000, you haven't unlocked the fun these bikes have to offer.

I'll let the 1100 owners comment specifically on your two questions, but in general you shouldn't have to rev it up beyond about 2,500 as you take off, and you'll probably find a nice spot at about 3,500 RPM that's a good target speed that gives you lots of room to accelerate.

--Mark
 
I am truly not disappointed at the knowledge out there. This really helps. Keep it coming!

Before the FatBoy I rode a V30 Magna which had a similar power curve. It red-lined at around 11,000 and really started to accelerate at around 6,000 RPM. I never got that bike above 70 mph, though. My new ST, however, climbs to 70 without me noticing -- in the 50 mph zones :eek::

The other great difference is that I have tach again. Riding the HD was all about sound, and it sounded the best at low RPMs (and at 60 mph all the vibration made my feet itch and the parts fall off!!). When I hear the ST climb above 4000 it "sounds" too wound up. But I will actively learn to love that sound!!

Thanks!!!
 
Go for a longer ride and you'll note that if you want to be able to get out of the way (in town or on busy freeway) you'll want to be above 3500 rpm.

In 5th on the long lonely roads I find that I'm *always* above 4500... ;)
 
5th gear above 4500 rpm...hmmmm....in our area I've been wondering what to do with 5th gear.
 
FatBoyNoMore said:
5th gear above 4500 rpm...hmmmm....in our area I've been wondering what to do with 5th gear.
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I think I might be able to help:
North on 97 to Hwy 2 East and then North on Coulee Blvd to the damn... I really enjoyed it from East to West a few years ago!

You might even see over 5000 rpm in 5th with ease on that route! :D
Please do not blame me if you get to visit with :policeST: :poPoST1: and get a performance award!!!
 
The noise you here is labor knocking. Usually caused by pre-ignition and/or the loss of hydrostatic lubrication. Crank shafts and camshafts actually ride in their bearings on a film of oil. Demanding power at too low of RPMs allows the crankshaft to loose this film of oil and ride metal to metal. Keep short shifting at 2k RPM and rolling on the throttle and you'll soon be looking for a new engine.

Ralph Sims
 
Yeah, rev that thing up a little! For me, 4000 rpm in 5th is about 85 mph on the speedo - but that's only 78 on the GPS.
 
Mark said:
North on 97 to Hwy 2 East and then North on Coulee Blvd to the damn... I really enjoyed it from East to West a few years ago!
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Mark -- you must be clairvoyant. This afternoon after chores I made a quick run with my friend on his Triumph Rocket III up to Sun Lakes and back. Lots of straight lonely roads. I retrained myself to keep above 3000 RPM and things went and sounded so much better. Going up the twisties in the gorge East of Orondo I kept it in 3rd at 5000 and she performed beautifully!!

Not sure what the RPM in fifth gear is at 105 mph (indicated) but it was somewhere north of 4500. Fortunately no :cop2: . This bike does triple digits way too easy. The old FatBoy was happy to stay below 70.

 
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BuddingGeezer said:
The noise you here is labor knocking. Usually caused by pre-ignition and/or the loss of hydrostatic lubrication. Crank shafts and camshafts actually ride in their bearings on a film of oil. Demanding power at too low of RPMs allows the crankshaft to loose this film of oil and ride metal to metal. Keep short shifting at 2k RPM and rolling on the throttle and you'll soon be looking for a new engine.
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Excellent explanation! Thanks Geezer. Yes...I want to change my riding habits away from the Hawg. I love her too much to abuse her.
 
Mine never goes much above 4.5k and I don't get the noises you describe.
Like you I've just come from a Vtwin, all be it a yamaha BT1100. I don't ride any different because of it.
 
FatBoyNoMore said:
But one thing has been plaguing me is a growling/clattering noise when I roll on the throttle to accelerate from low RPM's, like 2-2.5k. The sound is like a diesel pickup accelerating quickly but from the transmission, not the engine.
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2,000 rpm is not an unusually low rpm for an ST1100. No, its not the tractor that a Harley V-twin is, but its not a crotch rocket, either. The condition you describe is a sympton of incorrect carb synchronization. One cylinder is pulling harder than the others, which will actually make noise especially at idle. The ST1100 responds well to a REALLY exact carb sync, following the factory procedure exactly. I did mine for years with mercury sticks, thought it was fine. I recently went to an electronic sync tool which is far more sensitive. It made a huge difference.
 
CarSalesman said:
The condition you describe is a sympton of incorrect carb synchronization. One cylinder is pulling harder than the others, which will actually make noise especially at idle.
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I get no noise at idle. But I am getting an initial maintenance on it after buying it used and carb-syncing is on the list. Thank you.
 
5K in third in the twisties !:D Thats just where you want to be! Sounds like you're getting the hang of it now.
 
I came from a cruiser myself (VStar) and got a 1995 ST1100 about the same time you did, FatBoyNoMore!

It's an ADJUSTMENT, but you'll get it quick. I've found the engine doesn't like accelerating below 2500rpm. I'd prefer to keep it above 3000 while shifting. It's TOTALLY not like a HD. You don't want to race to get to 5th gear by the time you're doing 35mph. Heck, at 35, anything higher than 3rd gear and you're probably lugging the engine, which is probably the sound you're hearing.

Wind it out to about 3800 while moderately accelerating, and don't bother going to 5th gear unless you're above 55 or so.
 
This has been a very instructive post and I've basically retrained myself. Thanks all.

Now I'm on to learning better turning techniques for the twisities! All about getting the most out of a great bike, safely.

This is a great community!
 
Awesome FBNM!

I've ridden every day for the last four days, and I'm about to jump on and go get some lunch. The weather is BEEEEYOOOOTEEEEFUL here! 80 and sunny! Gonna be that way for the next couple weeks it looks like.

I'm grinning from ear to ear!
 
Just as a side note if you notice really only coming from full stop out of first gear your idle adjustment may be too low as well. I keep mine at about 1200 rpm hot. Which is a little high but makes low speed riding much easier.

When rolling through the shift pattern I normally shift between 4-6k rpm when cruising on the hiway the st seems to get the best mileage 3500-3800rpm but sometimes I have been known to cruise 5th gear 5k plus.....which really should include additional radar detector requirements which are not fool proof. Additional gas funds will also be required...:D:D
A couple hours at 100+ really cuts back mileage.
 
Sounds like you are getting used to the ST.....

Seldom do I get above second gear in town, around 30mph, 3000rpm, so 40mph on more suburban roads would be 3rd gear, again 3000rpm....... that way you need very little braking if using better anitcipation of the road/traffic conditions ahead.....

Once out of town the only time you need 5th gear is once you get on the open road above around 60-70mph....

Don't lug it, the bike doesn't like it mechanically and you can't accelerate out of trouble of required....
 
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