Saturday, June 3, 2017

Spark Plug Heat Ranges

When the space for the ceramic looks much deeper, there is actually more total insulation against the heat going out of the back of the spark plug and into the engine compartment. This determines the heat of the plug, not whether it's made out of iridium, platinum, copper, or even nickel like on my old 89 Yamaha XT600 Spark Plug. (Related video) 

In the case of my 2004 Nissan Frontier, I noticed that one of the old spark plugs was a colder temperature index of 5 instead of 9. On NGK's it's very easy to tell the temperature ranges as a 1 is coldest, a 9 is the hottest, like what is supposed to be in my Nissan Frontier, but this was a 5, which was probably making for a little spark knock as the spark plug wasn't staying hot enough, unlike it's 5 other friends who were doing more of the work. The slight miss of this engine for the last several years? Mystery solved!


Side note: I hate anti-seize. As it ages, it becomes anti-remove, or whatever you want to say about how it makes it hard to remove a spark plug!


What are some reasons you'd change your heat ranges? A lot of people assume hotter means more performance, but as you can see for my Nissan Frontier, they've already chosen the hottest plug. The truth is, you're not going to be able to do better than what the manufacturer decided you needed for the heat range of your engine unless you've done significant modifications, which may change the needs of your engine.

Most commonly, people go colder on the heat range of their spark plug because of forced induction, be it a super charger or turbo charger, with great over all engine temperatures, having a lower heat range on the spark plug can be a preventative against knock or more minor power losing per-ignition.

I've seen people do okay with a hotter plug a lot of times when they always short tripped their vehicle or for some reason the engine was staying too cold, but honestly, they're usually lying to themselves. I bought a more expensive plug, it's hotter? No, if you check how the manufacturer rates the heat ranges, you'll find it's pretty difficult to buy plugs that are even in the wrong heat range unless you do a special order, knowing how the numbers for that spark plug manufacturer and how they tell you what heat range it is.

Let's get back to why I say people are lying to themselves. You see, just because it's an iridium and it gets a better spark, it doesn't mean you've actually changed the heat range of your spark plug! That's spark. The heat range is the temperature of the spark plug when it's NOT igniting the fuel/air mixture.

If a visual and practical example, help you learn, be sure to check out my video about this below:

Saturday, February 25, 2017

VVT-i Explained

VVT-i, or Variable Valve Timing with Intelligence is Toyota's name for the subject at hand. Other manufacturers have other names for it.


Now, what's really fun, is that all modern cars having timing advanced adjustments on the fly, but being able to adjust the timing of when valves actually open and close is revolutionary for the time if you ask me.

Timing advanced, more fully explained, then what's in the video: spark timing, or timing advanced, can be changed at the flick of PCM's choice to generate more power. Under heavier loads, you can't have as much timing advance, or you get knock.

Timing advance is just a related point however. With VVT-i, changing when the intakes open and close was added more as a way to lower emissions, then it was to gain that much power. It really only gives like 5 points of bHP, or horse power at the crankshaft, and even less, only a few horsepower at the wheels. When it advances when the intakes open, it actually doesn't let the engine draw in as much fuel and air. This makes idling these cars much more efficient then their predecessor. This engine concept has been around since the 19th century, but only now can we have a more efficient engine AND a more powerful engine at the same time.

The other reason for better emissions however, is that a later intake means that the exhaust doesn't escape as well so it can be Toyota's way of not having an EGR system. The inert gases reduce combustion temperatures, decrease NOx, if this the example engine even is capable of making NOx, I'd be surprised, but these are the normal functions of EGR. On bigger, badder engines, without EGR, you'll pit your pistons, so let's not just hate the fact that they can clog up or make our intakes dirty. They have a valuable purpose for engine longevity as well!

And now to the YouTube segment today of our article!


Shown by a Toyota Corolla 1998-1999 vs 2000-2002 Engine - Chevy Prizms are the "same" except for these changes across those 2 year zones. What's really interesting, is this engine has a design change but it's the "same" car from 1998 to 2002. It's all the 8th generation of Corolla.

See a VVT-i engine versus the same one without!

By AutoBravado, also DE Nichols on YouTube.

Saturday, January 28, 2017

Part 2 2015-2017 WR250R/XT250 vs. the 2012-2016 Honda CRF250L

Yamaha WR250R

If you're taller and larger, this is the only choice. It has a superior suspension over it's younger brother the XT250 and the Honda CRF250L. If however your inseam is too short for this bike by more than 2
inches, then the Yamalink and stock adjustment for ride height won't be enough. If you're still heavier, then you may need to beef up the the suspension on the XT250 or just plan on upgrading immediately the Honda CRF250L. I've only seen offerings by a custom company, but they have a calculator based on your riding habits, weight, and more to get you the right suspension.

The Honda CRF250L Runs far better on dirt, it has less power on the freeway

It should have very similar range, but my friend and I both see a steady 53-55 miles per gallon, which is far less than either company reports by 19 to 17 miles per gallon. And I am referring to super gentle driving for an entire gas tank and trying to peel the tires off onto the payment. So if you don't care about gas mileage, other than the all important range issues these small bikes have stock, know this. Having as much fun as you can handle appears to have NO EFFECT on range!

Yamaha's WR250R  reported miles per gallon? 71. Real world? 53-55*; well, I did get 74 once when I went up a high elevation mountain and coasted more going down it (and I had to beat on the throttle hard with all the traffic on the way up). 1.9 gallons CA model tank capacity and 2.1 gallons for everyone else means 102.9 to 113.4 miles of range in my experience.
*confirmed on another review online as well; 54 miles per gallon

The truth may be that the Honda has more HP than I've been able to find hunting around online. It's barely slower than the Yamaha's 24.5 HP, but since Honda has a throttle stop built tighter in to protect it's engine for longevity and it has a very narrow range of RPM, which has full power, it will in effect be much slower if you go outside the computer's desired RPM range. Honda has 1 less torque, but it's torque comes in sooner than Yamaha's 8,400 RPM torque of 17 (2008-2014 figure - hard to find the torque for 2015 to 2017 - this engine has been beefed up, but by how much really? An exciting review online is hardly numbers, especially if they were supported by Yamaha to do the review).
Honda CRF250L's 71 miles per gallon. Real world? Same as the Yamaha with another approximately 200 lbs. man for 53ish miles per gallon.

2 seconds faster than the Honda CR250L in the 0-60! (1 websites report, personal experience says the gap is narrower, but there was no clock to prove by how much)


Yamaha XT250

While I didn't intend to review a motorcycle I hadn't rode, it's an honorable mention as it's a lot like it's big brother.

In comparison to the WR250R, this dream machine loses the 6th gear, adjustable suspension, ride height, and more. Ride height isn't a great loss part for some, and if you're lighter, this with a lower combustion engine, may not be a loss either. Power loss may not matter if you're smaller, you may still keep up just as well! Every motorcycle has a niche that it fills and this motorcycle should not be forgotten for it's being more affordable not just to buy, but the fact that it wants regular fuel. No premium fuel gouging or driving in an area where higher octane isn't available. Still, if the Honda fits you, you may not want to consider Yamaha's XT250, reliable HP figures are hard to come by, but this is seriously behind in the stats on paper for HP in comparison to the Honda CRF250L. Yet, while it does have lesser than the Honda CRF250L, some of the parts you may want on your XT250 could easily be obtained from the WR250R highly compatible parts list, while some aftermarket for similar upgrades on the Honda are very harder to find.


Honda CRF250 L Horse Power and Torque

I've heard reported as high as 22.8 HP on the CRF250L, but let's be honest, my buddy and I even swapping bikes always find the Yamaha faster, so if the CRF250L did have nearly the same HP, then it's not utilized as well. I did better confirm it's torque at 16.2 TQ. The torque figure makes sense. This was confirmed repeatedly by multiple sources. I find it silly that Honda and Yamaha official websites don't include this information. Honda having less torque than HP does make sense though, since these are meant to be higher revving engines. Yamaha only outclasses with 17 torque, but it comes on to late in the RPM to use the torque down low when your meeting difficult terrain. To have the higher rev range help you out of tough terrain can have your back end bouncing and juking underneath you, putting you out of control. It may not be just skill that gets my friend uses to outclass me up rough hills and terrain.

It's tires stock aren't as good for desert (mostly what I have available to ride on).

Remember to check out part1! Part 1 2015-2017 WR250R vs. the 2012-2016 Honda CRF250L

 - AutoBravado

Saturday, January 7, 2017

Part 1 2015-2017 WR250R/XT250 vs. the 2012-2016 Honda CRF250L

The Suspension Competition

The WR250R wins on suspension, but this and more 
goodies is why the WR250R costs more than the CRF.
Everything about the 2015-2017 Yamaha WR250R costs you above the CRF250L, but if you're a larger man, say 200 lbs+ (91 Kg+) the Honda's springs will slowly give out on you and you'll need to spend about $350 on custom springs to match the motorcycle perfectly to you (The bike is optimal for someone who is about 134 lbs. (~61 Kg)). I did some googling and I found an American company that'll take all your personal stats and build you appropriate custom springs. They give about 50% more spring support than stock, so for me and my friend in this bike get about 1/3 less of the spring support than we need. The Yamaha WR250R already has an adjustable rear suspension. It's meant for getting the preload right, but if you need to, you can lower the bike like I had to while still nearly retaining it's ride characteristics.

Ride Height and Transmission comparisons; Yamaha vs. Honda CRF250L

The 2012-2016 Honda CRF250L is a bit slower, but if you're a better rider you'll stay way ahead of me on my better Yamaha WR250R. The Honda comes with smoother power delivery, but without the EXUP (Exhaust Ultimate Power Valve) exhaust the power range is short in each gear giving you less customizable driving with that manual shifter. They both come with the 6 speed transmission, so if the WR250R's price tag has got you down, switch to the Honda over Yamaha's XT250. The XT250 only has 5 gears and if you ride on the freeway you'll be suffering, but if you need a shorter bike the XT250 or the CRF250L is a better way to go. The WR250R is a good 1/2 foot taller and stock than the shorter XT250 and CRF250L. I'm not only on my tippy toes, I'm dropping the motorcycle over as little of a slight impression in the road at a stop sign. I HAD to lower it. I have a 30" in seam. People say you can solve these issues by being a better driver...okay, how's being at a stop driving!?

If you're shorter the XT250 and CRF250L win in their stock from the factory form.


Lowering the Yamaha WR250R

When I can, I'll try out the Yamalink, which is a commonly sold lowering support so I can add more preload back into the adjustable spring rate (which also changes ride height). After a time, my motorcycle did settle into it's new lower position and get back to riding like it did. I know this because certain bumps that should hurt with the lower spring rate don't hurt anymore.

A video on how to adjust the spring system is still coming. The Yamaha WR250R wins again in it's adjustable spring rate. If you do serious dirt riding adjust preload is critical for your safety if you're going to be doing jumps, and it'll still very seriously change how the motorcycle rides. When I lowered it all the way, my first turn in the dirt almost had me crashing. I loaded more preload back in to where it was more drivable but it was still low enough so I was safe at stop signs. Don't get me wrong, I was okay if I had a HEAVY backpack on with extra fuel with how it came stock, but who always wants to ride encumbered? And my skills still aren't up enough that I can just never put my feet down. I took on a big steep hill one day. I didn't make it all the way up and I was panting with the effort to get turned around on a bike that I can't get my feet on the ground with (and realize I work out all the time, I'm fit, but trying to have strength while stretching your legs all the way out for length is a very difficult combination). If I had the XT250 or the CRF250L it would have been much easier, so while I will be making my motorcycle shorter and that does mean I can add more preload back in, I still won't be adding it all back in anytime soon.

 - By AutoBravado

Wednesday, January 4, 2017

Dual Sport Riding, 1989 Yamaha XT600 Introduction, and Introducing the 2017 WR250R

Introducing the 1989 Yamaha XT600



Cush Drive

For a big single stroke like this 600cc to deliver smooth power, a cush drive is involved to smooth out the action going to the wheels. :)
See this part of my Motorcycle Inner Tube Replacement or Repair, 89 Yamaha XT 600 video to see the Cush Drive.

1989 Yamaha XT600 statistics:

Crank HP 44
Gas mileage stock 44

Rear tire pressure 22, off-road 14


Dirt Riding Meets the Street, Dual Sport Riding!

Enduro riding is a way of trying to have it all. The city and the off-road, or as I call it, the dirt.
"What did you do this weekend?"
"I was in the dirt", I reply with a smile. :) The answer doesn't change, I'm happy.

Really, having a street legal dirt bike, an enduro or dual sport, is about trying to have everything. The streets and the off-road. You do sacrifice how much the wind hits you being high up on windy days, but you gain not loading your motorcycle into a truck all the time to enjoy a trail ride.

This is a sneak peak, you only know about this if you're following my website! Here's a brief raw clip, where I'm excited to not have to load up my old 1989 Yamaha XT600 up anymore in my Nissan Frontier to go for a ride:  
 

The issue was that the 89 Yamaha XT600 isn't a popular motorcycle anymore. Some vintage items are, and the parts are more readily available...I could be wrong. There are a surprising number of enthusiasts on YouTube, but playing with an old motorcycle is an expensive game when parts are very hard to come by so....I ended up getting a new one, lol. :) That video is still coming. We'll be nice and call it editing issues.

Long story short, my old 89 Yamaha XT600 kept being difficult to replace parts for, some of which would of helped me get street legal, so really, it was a off-road only experience instead of the dual sport that I was truly going for.

Introducing the 2015-2017 WR250R though an oil change, lol



The 2015 had an intake tube recall and 2016 had it right new. For the 2017 model, I heard they changed to a high compression engine but I've seen the same compression since 2008! And possibly the cause of dirtier oil. More blow by gases. EXUP exhaust seems also responsible for dirtier oil, but hey it also makes the bike more responsive at more and less RPM by adjusting exhaust restriction. People with aftermarket exhaust say the oil dirties slower.

Okay. I got excited. I'll drop the bold. More about EXUP exhaust (Exhaust ultimate power valve):
Exup exhaust is a valve controller that controls how much exhaust can leave the engine. This gives the WR250R way more control over how the engine is running. Sure, it is an emissions thing, but it also increase the performance of the engine all across the rev range. There is no perfect solution for how narrow or wide an exhaust is across all the rev ranges. With in stock performance, this is the best you can get. If you replace the muffler, will you have more power? Yes, but probably not at lower revs, because the aftermarket I've seen so far REDUCES low end torque. Sure, mufflers very, but they all, that I've seen, require removing the EXUP valve. Headers do the same thing to the bike. People who want the best drag racing motorcycle out of their WR250R somewhat missed the point of it's creation, and at this time, that seems the only way to upgrade in this region. To lose some of this performance in one RPM to gain some of performance in different RPM. So right now, I want none of it. I already bought the creme dela creme of current dual sports available under $10k. And the Husqvarna's above $10k need engine rebuilds constantly for all the power they pull out of little machines. The Honda CRF250L is reliable and dirties it's oil slower without EXUP or a high compression engine...but they also don't get the high compression engine or EXUP. It' a trade off, but other than higher fueling and oil change costs, you do get more performance with the cost of more oil changes. 
 - By AutoBravado