Motorcycle.com

DougandCarol · 11-17-2006, 12:07 AM

First Post - Uh? Tag your IT?

OK. Higher compression ratios also generate more heat, a limiting factor in air cooled engines due to pre-ignition. Also due to the additional combustion forces, the faster your bike wears out!

Dueducs · 11-17-2006, 01:19 AM

Who gives a flyin' fig if you're 1st or not.

If you have something worthwhile to say, then say it.

Otherwise... STFU !!!

rsk173 · 11-17-2006, 01:54 AM

telling someone to stfu while you're typing away pointlessly doesn't make you cool; it makes you an ass.

anrajala · 11-17-2006, 02:13 AM

Whether the engine has any compression rate at all is much more important than how much it is. Many an unsuspecting buyer has been hoodwinked into buying a bike without. Of course, without the compression rate there is not enough back pressure in the pipe causing deficiency of vibe.

When buying a bike, the first question should always be whether it has a compression rate. See if the salesperson has any hesitancy or sideways glances in answering, might be youÂ´d have to put a bit more pressure to get to the real truth.

- cruiz-euro

longride · 11-17-2006, 02:14 AM

Use the 'seat of the pants' spec sheet on any motorcycle you buy. Ride it first. That will tell you everything you want to know. It's worked for me. All the rest is for impressing the fellows at the Burger Barn.

longride · 11-17-2006, 02:17 AM

If you tell someone he's an ass while typing away pointlessly, what does that make them? I'm just askin'.

lionroyboy · 11-17-2006, 02:22 AM

The spec table seems to help me decide which bikes I'd like to take a closer look at when I'm in the market for a new bike and I've already read a road test or track test review and heard about the bikes' performance, comfort, and handling. Unfortunately, I know for sure that I don't have the skill to reach a bike's potential like the test riders do. So, I'm not sure how much their test ride results translate into which bike will perform and handle better when I'm the person at the controls! But, usually I'll use the spec table to look at the seat height, fuel capacity, dry weight or wet weight to help me compare between different bikes until I get the chance to see them in person. But, the spec sheet kind of gets tossed out the window for me once I get a chance to test ride the bikes I'm considering.

SRMark · 11-17-2006, 02:35 AM

Just keep reading. You'll eventually catch on to the meaning of rake, trail, wheelbase numbers (to gauge the bike's handling traits), compression ratio (relating to the engine's performance characteristics), valve arrangement and adjustment (yet another indication of the engines performance goals), final drive (ease of maintenance, performance intent, etc). Familiarity may bread contempt but it also breeds depth of understanding. Wade in and eventually you'll be swimming in the deep end.

The good folks at Wikipedia have a fairly good definition of Compression Ratio if you care to take a look.

seruzawa · 11-17-2006, 04:53 AM

Spec tables can be interesting and quite amusing. Some people from Seattle spend their entire lives in vicarious motorcycle riding entirely by means of spec sheets.

Especially hilarious are the dry weight claims... especially claims by Japanese manufacturers. They usually list the shipping weight which is without battery, fluids (icluding brake fluid) and even tires and then they subtract a few more pounds for fun. Some bikes weigh a hundred pounds more when put on a scale, ready to ride, than they weigh on the dry weight chart. Ignore dry weights.

Horsepower claims are also very funny. The distributers like to fudge the numbers. As an example back in the 60s Ducati's 250s used to magically increase in horsepower each year even though no changes were made to the bikes. Trust only the dyno numbers that you can find in the various mags.

pplassm · 11-17-2006, 05:17 AM

The specifications can be of use if know what you want.

For example, I have a Suzuki DRZ400S. It's compression ratio is significatly less than it's off road only sibling, the DRZ400E. This matters to me, as I like to use regular 87 octane gasoline. 92 octane is recommended for the higher compression engine. I have often found myself in situations where only low octane fuel is avaialable.

This also means that the lower compression engine will be down on power compare to the higher compression engine, but I can live with that.

11-17-2006, 12:07 AM	#1
DougandCarol Founding Member Join Date: Jun 2007 Posts: 38	Re: MO Reader Question: What's in a Spec Table? First Post - Uh? Tag your IT? OK. Higher compression ratios also generate more heat, a limiting factor in air cooled engines due to pre-ignition. Also due to the additional combustion forces, the faster your bike wears out!

11-17-2006, 01:19 AM	#2
Dueducs Founding Member Join Date: Jun 2007 Posts: 19	Re: MO Reader Question: What's in a Spec Table? Who gives a flyin' fig if you're 1st or not. If you have something worthwhile to say, then say it. Otherwise... STFU !!! __________________ Motorcycling... what else is there?

11-17-2006, 01:54 AM	#3
rsk173 Founding Member Join Date: Jun 2007 Posts: 65	settle down, francis! telling someone to stfu while you're typing away pointlessly doesn't make you cool; it makes you an ass.

11-17-2006, 02:13 AM	#4
anrajala Founding Member Join Date: Jun 2007 Posts: 1,490	Re: MO Reader Question: What's in a Spec Table? Whether the engine has any compression rate at all is much more important than how much it is. Many an unsuspecting buyer has been hoodwinked into buying a bike without. Of course, without the compression rate there is not enough back pressure in the pipe causing deficiency of vibe. When buying a bike, the first question should always be whether it has a compression rate. See if the salesperson has any hesitancy or sideways glances in answering, might be youÂ´d have to put a bit more pressure to get to the real truth. - cruiz-euro

11-17-2006, 02:14 AM	#5
longride Super Duper Mod Man Join Date: Nov 2001 Location: Anywhere they let me Posts: 10,484	Re: MO Reader Question: What's in a Spec Table? Use the 'seat of the pants' spec sheet on any motorcycle you buy. Ride it first. That will tell you everything you want to know. It's worked for me. All the rest is for impressing the fellows at the Burger Barn. __________________ I'm a knucklehead

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11-17-2006, 02:17 AM	#6
longride Super Duper Mod Man Join Date: Nov 2001 Location: Anywhere they let me Posts: 10,484	I'm just askin' If you tell someone he's an ass while typing away pointlessly, what does that make them? I'm just askin'. __________________ I'm a knucklehead

11-17-2006, 02:22 AM	#7
lionroyboy Registered Member Join Date: Jun 2007 Posts: 25	Re: MO Reader Question: What's in a Spec Table? The spec table seems to help me decide which bikes I'd like to take a closer look at when I'm in the market for a new bike and I've already read a road test or track test review and heard about the bikes' performance, comfort, and handling. Unfortunately, I know for sure that I don't have the skill to reach a bike's potential like the test riders do. So, I'm not sure how much their test ride results translate into which bike will perform and handle better when I'm the person at the controls! But, usually I'll use the spec table to look at the seat height, fuel capacity, dry weight or wet weight to help me compare between different bikes until I get the chance to see them in person. But, the spec sheet kind of gets tossed out the window for me once I get a chance to test ride the bikes I'm considering.

11-17-2006, 02:35 AM	#8
SRMark Founding Member Join Date: Jun 2007 Posts: 1,465	Re: MO Reader Question: What's in a Spec Table? Just keep reading. You'll eventually catch on to the meaning of rake, trail, wheelbase numbers (to gauge the bike's handling traits), compression ratio (relating to the engine's performance characteristics), valve arrangement and adjustment (yet another indication of the engines performance goals), final drive (ease of maintenance, performance intent, etc). Familiarity may bread contempt but it also breeds depth of understanding. Wade in and eventually you'll be swimming in the deep end. The good folks at Wikipedia have a fairly good definition of Compression Ratio if you care to take a look.

11-17-2006, 04:53 AM	#9
seruzawa Robby Join Date: Nov 2001 Location: 8501 ft. Posts: 16,803	Re: MO Reader Question: What's in a Spec Table? Spec tables can be interesting and quite amusing. Some people from Seattle spend their entire lives in vicarious motorcycle riding entirely by means of spec sheets. Especially hilarious are the dry weight claims... especially claims by Japanese manufacturers. They usually list the shipping weight which is without battery, fluids (icluding brake fluid) and even tires and then they subtract a few more pounds for fun. Some bikes weigh a hundred pounds more when put on a scale, ready to ride, than they weigh on the dry weight chart. Ignore dry weights. Horsepower claims are also very funny. The distributers like to fudge the numbers. As an example back in the 60s Ducati's 250s used to magically increase in horsepower each year even though no changes were made to the bikes. Trust only the dyno numbers that you can find in the various mags. __________________ I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched c-beams glitter in the dark near the Tanhauser Gate. All those moments will be lost in time, like tears in the rain.

11-17-2006, 05:17 AM	#10
pplassm Founding Member Join Date: Nov 2001 Posts: 3,875	Re: MO Reader Question: What's in a Spec Table? The specifications can be of use if know what you want. For example, I have a Suzuki DRZ400S. It's compression ratio is significatly less than it's off road only sibling, the DRZ400E. This matters to me, as I like to use regular 87 octane gasoline. 92 octane is recommended for the higher compression engine. I have often found myself in situations where only low octane fuel is avaialable. This also means that the lower compression engine will be down on power compare to the higher compression engine, but I can live with that. __________________ Mongo just pawn in game of life.