Motorcycle specific questions

[Jonathan6229]

So, as long as I'm trying to (mildly) hypermile my ex-500, I have a few basic questions.
1. how long do you need to be at a stoplight to break even with shutting the engine down?
2. is DWB going to wear out the clutch since you have to hold in all the time?
3. is pulse and glide going to net big returns? (just asking, I'm not a huge fan of the method.)
4. I'm having some trouble finding anyone that has rejet ex-500 carbs for FE. Most kids try to get more power with rejets, so any input or projections on if that helps would be handy.
5. What else am I missing?

Thanks the help guys.
Jonathan

[renault_megane_dci]

2. misunderstanding of the acronym I believe, DWB is Drive Without Brakes, you don't need to use the clutch for that.
Maybe you were thinking about coasting ?

What I did was shift early and try not to ride too fast.

On top of that you could go for a sprocket change (bigger front, smaller back) to have the engine spin slower for a given speed and have the engine under more load (which means more throttle hence less pumping loss)

Re-jetting is not gonna do wonders, they are quite lean to start with for emissions control.
Actually I recall reading about a BMW R100 that picked up a few mpg with "power" jetting.

[Jonathan6229]

Originally Posted by renault_megane_dci

2. misunderstanding of the acronym I believe, DWB is Drive Without Brakes, you don't need to use the clutch for that.
Maybe you were thinking about coasting ?

What I did was shift early and try not to ride too fast.

On top of that you could go for a sprocket change (bigger front, smaller back) to have the engine spin slower for a given speed and have the engine under more load (which means more throttle hence less pumping loss)

Re-jetting is not gonna do wonders, they are quite lean to start with for emissions control.
Actually I recall reading about a BMW R100 that picked up a few mpg with "power" jetting.

specificlly, wouldn't the DWB method be to pull in the clutch so you can coast the most distance? or do you coast up to a stoplight by just closing the throttle?

I've gone up 1 tooth in the front, and the bike acts like can go more, I did find "Gearing Commander" from this fourm, so when I figure out the best RPM range to cruise at, I can gear it maybe a touch higher.

Random question, how much does having the front fairing removed cost? (I was patching the plastics)

[sendler]

Coasting is good for ecomomy and driving without brakes is another way of saying you anticipated the road and used only enough gas to coast up to the next stop. Which is also a form of PnG around town. Coasting will not hurt the clutch even though it is utilizing the throw out bearing more than usual. Pulse and Glide works. More so on a bike like my Ninja250 which has ridiculously low gearing. At least then it isn't spinning 9,000 rpm all of the time you are droning down the highway. It is good for about 15% on that bike. Less for the CBR250R which has longer gearing than stock.

[jkv357]

Originally Posted by Jonathan6229

So, as long as I'm trying to (mildly) hypermile my ex-500, I have a few basic questions.
1. how long do you need to be at a stoplight to break even with shutting the engine down?
2. is DWB going to wear out the clutch since you have to hold in all the time?
3. is pulse and glide going to net big returns? (just asking, I'm not a huge fan of the method.)
4. I'm having some trouble finding anyone that has rejet ex-500 carbs for FE. Most kids try to get more power with rejets, so any input or projections on if that helps would be handy.
5. What else am I missing?

Thanks the help guys.
Jonathan

I think with a cycle you don't have as much ability to stretch the mileage as you do with a car. A lot of the mileage potential has to do with the engine's basic design - either it's efficient at cruising or it's not.

I'm familiar with the EX-500 (raced one back in the day...) but not sure which category it falls into.

The cycle I ride now (SV650) is pretty good, even without using any special techniques. I've got 50+ in city riding and 60s on mild backroad riding. Even with no fairings it gets 55 or so on Interstate riding over 70 mph. I've geared it up 1T on the countershaft, but I don't think it has gained much as far as mileage from it - just a smoother cruise. Overall, the basic engine design is good for efficient cruising, it's not anything I'm doing.

I don't P&G, as it has a ton of engine braking. I don't coast with the clutch in, mostly because I don't like it.

Get your acceleration done fairly quickly and get in top gear, then make sure you just have enough throttle opening to maintain your speed. Watch the throttle opening, not just the RPMs. Bogging in a higher gear will get you less MPG than spinning faster in a lower gear at a smaller throttle opening.

As far as jetting, jet it to run as good as possible. Leaning the jetting doesn't always help get good mileage. You want it running at its best efficiency.

Run 87 octane without Ethanol. Use a synthetic engine oil with a 5W low-end rating. If it recommends 10W-40, using Rotella T6 5W-40 will help mileage.


Jay

[renault_megane_dci]

Originally Posted by Jonathan6229

specificlly, wouldn't the DWB method be to pull in the clutch so you can coast the most distance? or do you coast up to a stoplight by just closing the throttle?

I've gone up 1 tooth in the front, and the bike acts like can go more, I did find "Gearing Commander" from this fourm, so when I figure out the best RPM range to cruise at, I can gear it maybe a touch higher.

Random question, how much does having the front fairing removed cost? (I was patching the plastics)

Removing the fairing impact depends on your average speed.
Airflow behind you is more important than in front of you.

A 500 is not gonna help you very much identifiying FE potential since it is so much powerful already.

[alvaro84]

Originally Posted by Jonathan6229

So, as long as I'm trying to (mildly) hypermile my ex-500, I have a few basic questions.
1. how long do you need to be at a stoplight to break even with shutting the engine down?

I have no exact data, it's said it's a few seconds. You can gain extra seconds by using the kill switch way before stopping, if traffic permits. You should watch your battery, though: I've just drained mine by coasting too much with the engine off (I commute in a hilly area) and using the starter after these sessions. Bump starting helps quite a bit, but Teresa is not that smooth to bump start - a 650 single won't ever be, it seems.

2. is DWB going to wear out the clutch since you have to hold in all the time?

I coast a lot. It won't wear clutch plates, our current set has already lived longer than the previous one I inherited from the first owner. But the dropout bearing died at 111000 km. It was dirt cheap, it just needed draining the oil and coolant to get it replaced. I continue to coast a lot, needless to say. Whenever I need to lose speed, I coast. And yes, in a city it effectively makes the trip a nice example of P&G.

3. is pulse and glide going to net big returns? (just asking, I'm not a huge fan of the method.)

Even though Teresa doesn't rev too fast (4000 at 100km/h|62mph), it does help a bit. But coasting to slow down seems to be more essential than making artificial occasions to do it. My record tanks definitely have a lot of P&G, but I have good tanks with long, steady speed (highway) legs too, where I only coast to slow down and P&G downhills, where the engine load would really be too low. And in lower gears, I always P&G below 4th!

5. What else am I missing?

You didn't quite miss it, but a taller ratio by replacing the front sprocket helped a lot with our other bike (Hyosung GV250 named Ciliegia).

[Jonathan6229]

OK, I have a few questions about aeromods, but not really enough to warrant starting another thread.

I'm limiting alot of what I would be willing to do, for example, no giant boat tail, or huge windscreen. And I realize thats somewhat counterproductive, as (some of us) make huge gains by using funny looking fairings.

So, is it unstable if I want to completly fair in the wheel? I'd like to do something with it, but people keep mentioning crosswind stabilty. Any thoughts?

Should I just look to clean up the stock fairing assembly as much as I can?

What do you guys do for mirrors? mine just hang out in the wind, and bother me.

[beatr911]

Making some apparent reductions in drag from the mirrors, turn signals, etc. will be minimal at best. Probably not measurable. Don't fair in the front wheel only, it will negatively affect the stability of the steering in cross winds and will give only small gains by itsself. If you try it anyway, just make sure the wheel fairing is rock solid, you don't want it coming loose!

By far, the largest contributor to aero drag is you. You are also the easiest to change.

Wear riding gear that fits well and doesn't flap in the wind or create a larger than necessary obstacle for the wind. Tuck down when you can reasonably do so. Place any baggage you have inline with your body like a tank bag or rear trunk, panniers are awful and increase drag alot.

Kawasakis of that era sometimes have overly large main jets to compensate for overly lean primaries and needles for emissions reasons. If you want to play with jetting don't guess, please use an O2 sensor and a gauge to get it right. Best fuel efficiency is right about stochiometric 14.7:1 or just slightly lean like 15:1, an inexpensive narrow band O2 sensor will work fine to target this area.

+1 for using only the RPMs required to produce the power you need.
+1 for taller gearing, it also doesn't affect daily riding performance much if at all, most who try it prefer it.
Keep the chain well lubed, use a non o-ring racing (good quality) chain for the lowest drivetrain friction when you need to replace the chain next time.

Dress appropriately and ride as much of year as possible. Enjoy it, motorcycles are one of the most resource efficient means of transportation we have.

[star_deceiver]

The aerodynamics of the bike and the combined weight of rider/bike will make the biggest difference (tuck down on the highway and hit the gym to remove the spare tire). Taller gearing can help, but don't overdo it.

Don't buy cheap chain!

The 428 cheap, non-Oring chain on the CM185 might last 3000kms before it's stretched beyond useable limits. Then it and both sprockets will need to be replaced. Yes, it's very well lubricated.

Meanwhile, the 520 Oring chain on the KLR has lasted over 27000kms, isn't stretched beyond it's limit. The rear sprocket isn't that worn, isn't hooking and probably wont need to be replaced when it comes time to replace the chain (although I'll probably change it out anyways). The front sprocket (aftermarket geared +1) is starting to show wear and I'll replace it when the chain gets done. And yes, the Oring chain gets very well lubricated too.

You are not competing in the super GP... you do not have the skill, feel or talent to use the infinitesimal gain (for performance or FE) that a lightweight chain will provide. A lightweight, cheap chain will stretch quickly. A chain stretched beyond its usable limit could jump teeth on your sprockets and break which will, at best, leave you stranded and at worse ball up on the drive sprocket and rip a nice hole in your engine...

In summary:

Lose 20lbs, improve your aero, and buy quality parts that will last a long time.