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Smoother low revs.

9K views 84 replies 22 participants last post by  Finally home 
#1 ·
What is the best way to make a '97 900SS more smoother at low revs?

When I use the bike to go to work I have to ride at the speed limits because of the camera's and 'traject controles' (you get timed between to camera's which are a few kilometers apart).

Max speed is then 70km/h (45miles/hour). When passing villages it's 50km/h (30miles/h).

So most of the time I'm in low revs and the SS doesn't like that. Especially not when lower than 3000 rpm.

Is there a way to get the bike run smoother at low revs? I've read good stuff about Ignitech ignitions. Would that help? Another thing that's been suggested is a larger rear sprocket (39 instead of 37) too make more revs at the same speed.

Any alternative solutions, suggestions or experiences are more than welcome!!

Thanks!!
 
#48 ·
There is a reason Ducati riders name their bikes after women: Stress from the relationship. The reason I changed ignition components is age. Plug wires, caps, and plugs don’t last forever. If you don’t believe me, next time it’s raining, grab one of them with the engine running.
 
#49 ·
There is a reason Ducati riders name their bikes after women: Stress from the relationship. The reason I changed ignition components is age. Plug wires, caps, and plugs don’t last forever. If you don’t believe me, next time it’s raining, grab one of them with the engine running.
No thanky, i was taught hands off electrical long ago, as toddlers my sister shoved a fork into an electrical outlet (long before advent of childproof plastic guard inserts)...old man went semi-ballistic with a speech on both good and bad of electrics...instilling both a respect and fear of electrics present to this day in this old boy.
 
#56 ·
Still thinking about an Ignitech anyway.
It's not that expensive (As I'm living in Europe, I can have it shipped from Ignitech for around €150).

And I once was on a dutch Ducati forum and read some great reviews about Ignitech there.

I don't expect miracles from the thing but just thinking about the theory behind it, it may be a good investment I hope.

We'll see...

I keep you posted if I should buy one.
 
#57 ·
I never do track days and 75% of the time I use to bike to commute at speeds around 50 to 70 km/u.
So Ohlins and light wheels will be some kind of overkill for my bike I guess.
Just to clarify that yes at those speeds the wheels are not going to be a huge benefit.
I do often hear the belief that you need to be a racer or some such thing to benefit from good suspension, this is far from the truth. Suspension helps stabilize the bike and add comfort to the ride as well. those cobblestones would feel better if the suspension absorbed them instead of transmitting every one to your seat,footpegs and handlebars. Simple fact racers need suspension to be stable to allow them to be consistent but road riders also benefit from not having the bike dive and pitch over bumps and when brakes are applied.

You can set suspension to feel every pebble for that person trying to feel for those last bits of tire traction or to run over bumps and not transmit anything to the rider. This makes the ride more comfortable and less fatiguing with the added benefit of a bike that turns more predictably and safely. You do not need to spend huge money to get good suspension but 90% of the time it should be the first place you spend money after the bike is properly maintained.

Really the reason to do Ohlins and wheels is if you find them used they often are the cheapest modification you can do with a noticeable benefit. If you wantch the classifieds here you will see someone just sold a set of forged aluminum (light weight) wheels for about $1500 in about a week. Those wheels new are about $2000 new so if you bought them new you would have lost about $500 but the guy who bought them used will likely lose nothing when they are resold. If in good shape they should sell for about the same price in 5 years or 10 years so though the money is parked in the wheels the cost of ownership should be about zero.

Used Ohlins have similar resale especially on rare/old components as more new people are fixing /building Supersports. For modern bikes these prices are not high at all ($3000-$6000 exhausts today) so this will continue to drive prices of sought after parts higher. I have customers who are able to sell wheels they bought from me 10 years ago new for more than they paid.

I still would do the suspension next.
 
#58 ·
I might do the suspension if I find a nice deal on some used Ohlins or any other good quality brand.

A few weeks ago I came across a Ohlins DU-235 (for the SS) in nearly new condition for only €400. They were sold by a guy who trades in second hand Ducati parts in the Netherlands.
I found these while I was having lunch at work (at 3a.m., I always work nightshifts) but could not make a payment with the computer (some security-settings from my boss did not allow that).
So i checked again when I came home (6.30a.m.) and apparently they were sold between 3a.m. and 6.30 a.m...

So yes, if I can find a good deal on some Ohlins, I might get them but it's not the most urgent part I'd like to replace since I'm quite happy with the stock suspension (which has a hyperpro spring in the back) after some experimenting with the settings.

And then again, the bike isn't the only thing to spend money on. I' married, two daughters (one in high school), 3 cars, a bike, a house, half an animal-zoo, my music instruments... So you can imagine I have no problem spending my money.
Choices have to be made and right now, I rather spend my money on holidays and city-trips with my family as my kids will not always stay with mamy and dady.

I like the Duc very much but it's far from the most important thing in my life. And I don't have access to an unlimited budget...
 
#59 ·
You don't have to go all out with Öhlins stuff to noticeably improve your suspension. The stock setup is so unbalanced that even springs alone make a huge difference. Most people also never service their rear shock, and after 20 plus years it would be a miracle if the dampers still worked properly.


I did racetech gold valves and springs, in the front and back. The front can be done in any reasonably well equipped home workshop, the rear I chose to send away. Total cost was less than any aftermarket shock I could find, let alone öhlins. The bike is noticeably better to ride anywhere, and totally transformed on a twisty road
 
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#60 ·
Yes what he said....

The Ohlins is good and has resale oem will never have but functuion wise just a set of springs get you 75% of the improvement. If you have the rear sprung did someone also valve it when they sprung the shock? often times when someone was tearing into a carby shock they would valve especially once they saw what valve was in it. If you have a valved and sprung showa you should be quite happy. Also it is/was common when someone did one end they soon saw the value in doing the other so many bikes started with just a spring and soon had complete suspension re-do.

I have 2 kids at home myself so I fully get dividing the pie for both time and money, always a challenge. No one is saying you need to do any work all at once we are just nudging you in a direction that has worked for us when you do get the chance. I hunted and saved for 10 years to get my first set of magnesium wheels and have always found there is a relationship of parts become available when we can least afford them. Simply make a list of wants and if AT SOME POINT you come across a deal know the value in picking them up.
 
#63 ·
I found that just reducing the viscosity of the fork oil from 7.5 to 5.0 made an enormous difference.
As standard, IMHO, the forks are way too harsh on these bikes...
lol... given your name "old rider" that is/was the classic modification done with damper rod forks back in the day. It still can work just fine and if the setup works for you then there is no harm . Where it is/was an issue is changing to a lighter oil means less dampening in both directions (rebound and compression) which often are at odds with each other.

We want a more soft high speed compression so the lighter oil helps on sharp edged bumps.
But the lighter oil can allow the lowspeed compression to dive more and the rebound to pop up too fast.
If you have stock springs some added preload can help with slowing the additional dive by increasing the force needed to start the spring moving , it also will put softer coils in coil bind earlier transferring to a stiffer rate sooner.
Changing spring rate or running the spring more on the stiffer portion of the range may show a lack of rebound with the lighter oil.
running stiffer rate springs will allow less oil/air spring and give you a softer ride mid stroke of the suspension, if you run the too soft oem spring you should not do this as the springs are soft enough to hard bottom.
 
#66 ·
https://www.revzilla.com/motorcycle/g2-throttle-tamer

G2 Throttle Tamer

G2's challenge was to improve control of over-responsive power characteristics of most fuel injected motorcycles. Their solution is the throttle tamer.

The Throttle Tamer incorporates a non-linear ratio between hand throttle rotation and carburetor or throttle body opening. The pulley, or as they call it, cam, pulls the throttle cable as the rider rotates the grip/tube. By altering the conventional, circular shaped cam, a vast improvement in control is achieved.

The Throttle Tamer has a cam with a reduced radius initially, which requires a slightly farther rotation to achieve the same carburetor or throttle body opening position as a stock throttle. This virtually eliminates the jerky throttle snatch especially evident in modern fuel injected street bikes. The radius increases or ramps up after ½ throttle to keep overall rotation required to reach full throttle at or near stock rotation.
Features:

Machined from 6061 aluminum in the USA
Self-lubricating Delrin bushings at each end of tube eliminate aluminum-to-aluminum contact and provide an ultra-smooth feel
Included cam is removable and can be replaced with alternate cams (sold separately) to fine tune control
Fits inside the stock throttle housing to stock cables
Works with all known aftermarket cruise controls
Slide your grip unto the Throttle Tamer
Installs in minutes

Made in the USA
 
#68 · (Edited)
Since this thread twists and turns,....

I have the Motion Pro fancy throttle (on FCR's) - which gives you a couple of choices on the throttle cam - I use the one with reduced initial action which keeps me from whacking it open until I really mean it. For me it is a driveability thing on the street, but also gets my wrist in a comfortable position for every motion on the track where it is WOT almost all the time. On the track it doesn't have much finesse above 6k rpms, (the rear tire slipping provides that!)... but I appreciate the exactness lower down in the revs for stop n go traffic in town.

Edit* re-read WED's comment above - and yeah, if there was one thing I would change about the fancy Motion Pro package would be to increase the "smoothness" of the action. At times even when the cables properly adjusted with tension, I would like to have smoother movement inside the grip itself, I've thought it needed a dry or wet lube in there,... is that what you mean by "slider"? I can feel the "sticky" is in the grip barrel and not the cables or the cam.

I dunno how else to describe it but its almost like the plastic tube is too big for the bar ("feels like", I don't know that it is) and so it has a rotational air gap that cannot be adjusted out. This undesirable effect comes and goes depending on how consistent forward horizontal pressure is on the bars. If I release it, (popping up for a looky-loo), the gap comes back which requires an initial increase in twist in either direction to control the gas. Constant pressure forward head down during operation of the throttle up and down won't show this effect, tight all the way.

Perhaps Thanos gloves "Infinity Gauntlets" might help?
 
#72 ·
I have not seen most bikes through my shop benefiting from changing these components.
Key part there is
I have not seen
There may be a great improvement but it has never been noticed or desired based on what people had the bikes in the shop for. Maybe the bike in question is abnormally rough at low rpms or maybe the rpms are abnormally low or even the owner being abnormally sensitive to a rough bike. All are somewhat subjective and hard to know from a internet post.

Maybe I am lucky that the bikes I see are all abnormally smooth due to my special tuning ability:grin2:
Low rpm smoothness is not a common complaint I hear so I do not want to mislead readers to think it can not be improved with a ignitec etc just that it has not been attempted. most ignitec's I deal with are straight to the track and are used to be a cheaper/easier alternative to kokosan boxes. maybe someday I will experiment with trying to make a bike as smooth as I can at lower rpms that I normally do.

Do they make throttle tamers for carby bikes too?
I have customers who have them and like them it is just upside down to me as we always used to want a faster throttle.
 
#75 ·
Maybe I am lucky that the bikes I see are all abnormally smooth due to my special tuning ability:grin2:
Even in that case I think it's cheaper for me buying an Ignitech instead of buying you a return-ticket to Belgium. ;-)

And just to be clear about this: the low rev smoothness is just something I'd like to improve if possible.
If it's possible; great! If not; I'll live with it.

Low rpm smoothness is not a common complaint I hear so I do not want to mislead readers to think it can not be improved with a ignitec etc just that it has not been attempted. most ignitec's I deal with are straight to the track and are used to be a cheaper/easier alternative to kokosan boxes. maybe someday I will experiment with trying to make a bike as smooth as I can at lower rpms that I normally do.
Most Ignitech ignition curves that I've seen are rather the same as the Kokusans in the higher rpm-range. So for track bikes I think the main reason for using Ignitech is, as you said, the price and the ease of use.


Do they make throttle tamers for carby bikes too?
I have customers who have them and like them it is just upside down to me as we always used to want a faster throttle.
Until these things were mentioned in this thread, I've never heard of throttle tamers.
So don't ask me who makes them and why and how and...
I don't think it's something I would like to use.
 
#74 ·
I have been driving 2 stroke dirt bikes since I was 10 years old so I know what you mean.

But that's not an argument to stop me in my search for a as-smooth-as-possible-ride-with-a-2-valve-Ducati.

It's not because there are bikes that are even worse at low revs that I should be happy with the way mine is at low revs.

If there is no way to make the bike run smoother at low revs, it's not a big deal to me. I'm not gonna sell the bike in that case.

But just asking doesn't hurt anybody so...
 
#77 ·
It finally stopped raining so I gave my new front sprocket (14T instead of 15T) a try yesterday.

Just what I was looking for!!

When cruising at 50, 70 or 90km/u I'm around 3000rpm and at that revs the bike runs great. With the 15T sprocket I was around 2500rpm and the old lady didn't like that. If I downshifted the problem was solved but then I was to high in revs to cruise through towns at 6a.m. (my Bos-mufflers are kinda loud soo early in the morning).

I'm just gonna see how she reacts on the highway (120-130km/u) and if that's still okay (not too high in revs to be comfortable) I'm gonna leave her like she is right now.

I'm glad I tried a €20 sprocket before spending my savings on +€1000 Keihins.
For what I use the bike, it's good enough like it is for now.

But knowing myself (always trying to enhance my rides) I think that one day in the future Keihins will be on my shopping list again. But that's okay. I rather make an improvement to the bike every year then everything all at once. That way, I can have fun for many years to come.

Anyway; thanks for the advice on this subject to anyone who made a comment in this thread!! Much appreciated!!
 
#80 ·
You misunderstood. The chain is much closer now. If you don’t keep a close watch it will chew into things that it shouldn’t chew into. Consider a larger rear sprocket and going back to the 15T in front when you need a new chain. The new chain will , of course, have to be longer to accommodate this.
 
#81 ·
As mentioned at some point it would be best for a couple reasons to do your gearing with the rear and return to a 15t front sprocket. Until then you should be fine with the 14t asd i have never changed a worn out chain slider due to running one. It was/is a common mod and though the SS never came factory with one it's not that different from some models that did.

If you start with a longer than oem shock so you have a steep swingarm angle and you run a 14t front the chain will rest on the top leading edge of the swingarm, until you sit on the bike. this is a common track setup and we still do not see increased wear from running these angle in part due to the slider gaining clearance as you use suspension travel.

On another smoothness note I am in the process of changing flywheels on a 1200 multistrada, the stock flywheel is almost 9 pounds! I think They were trying to make this bike smoother at those super low rpms figuring with the amount of power it has most riders will spend the majority of the time at sub 5000rpms. Bruce Meyers was hypothesizing that due to the super lean emmissions they may need the extra weight to keep them from stalling but the 1200 monster has a normal flywheel. That is a lot of weight to be slinging around outboard of the main bearings at high rpms. I am fitting up a slightly modified 4 pound flywheel as the customer was nervous of dropping to 2 lbs.

Makes you wonder if the majority of riders of big bikes seldom use the power why they want it so bad? I still find my air cooled motors to be just fine for road duty but then I do not live where speed limits don't matter and there are loooonnnngggg stretches of straight road.
 
#82 ·
I noticed the chain touching the chain guard on the swingarm but as you said, it seems okay when I sit on the bike. I don't have the longer SSie shock, just the stock one.
I might change the front sprocket back to a 15T but only when I have to replace the chain and right now it's nearly new.
For now I'm running a 14-37, when changing chain and sprockets I'll condider a 15-39 or 41.

But for now, I thought the best way to try a different gearing was by changing the front sprocket (no need for a longer chain). If I didn't like it, I just spend €20 instead of +€100 on a new chain and sprockets.

I'll keep a close watch at the chain guard and make sure my chain is set to the correct tension.

I don't expect big problems but I'll keep an eye on things.
 
#83 ·
I found this old thread while googling how to get my Bimota Mantra (Ducati 900 carb engine 1998) to run smooth at low revs. Lots of good ideas like FCR 39 carbs well balanced, Ignitech ignition, gearing, new chain and sprockets, new coils leads and plug caps, new spark plugs....

Here are I few ideas were not touched on....

1. Clutch design and wear and it's effect on the drive line free play... the hammering back and forth of the clutch at low engine speed causes the bike to not run as smooth as it could. The solution (part one) is new clutch parts, basket, centre and frictions plates to minimize the slack. To solve the design aspect you need to fit one of the "quiet clutch mods" which help hold the clutch pack from slamming back and forth at low engine speeds and smooth out the bike a lot.

2. Ignition timing and cam timing.... these can be adjusted to give better low rev running. For the cam timing you will need adjustable cam belt gears. At least to get them dialed in exactly in time with each other.

3. Twin plug heads will also help some say to a degree....

I am looking for more ideas!
regards
Gavin
New Zealand
 
#84 ·
Here is the list I have put together to get a carbed Ducati to run smoother at low revs. In the rough order that I would do them.... some have a very small effect, some a larger effect.... some cheap or free, some crazy expensive.... :)

Lower gearing.

Balance carbs.

Dynojet kit for standard carbs.

New chain & sprockets.

Light weight chain.

New clutch parts, basket, centre & friction plates.

"Quiet clutch mods" which stop the clutch pack from slamming back & forth.

FCR 39 carbs.

Ignitech ignition, or any good ignition with adjustable maps.

Ignition timing can be adjusted to give better low rev running.

New coils, leads, plug caps, & spark plugs.

Keep standard weight flywheel or increase weight.

Cam timing, adjustable cam drive gears to set perfectly in time with each other or advanced for low rev running.

Twin plug heads.

Engine balancing internally.
 
#85 ·
I certainly have had experiences like you driving through small villages while being very careful to observe the posted speed limit. In CH they pride themselves in exact speed measurement and there's no questions about calibration of their equipment if they catch you. They confirm the accuracy - "equipment error = zero". So my '95 SS-SP went to a 39 rear sprocket and it worked very well for over 4 years while I lived over there.
 
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