Topic: 550 rpms at speed?

[crazypj]

Borrow a GPS unit and check it.
 probably have 37t rear, fit a 34~35
 My little pick up runs between 3~7mph fast (fast speedo is still cheaper than a fast engine  )

[TwoTired]

The bike always felt frantic at 65 because it was pushing the rpm's really hard.
Sorta clueless at this point.

If you are running pod filters and/or non-stock exhaust, then maybe it's that the bike just *sounds* frantic.
Prolonged loud exhaust (or intake) noise is physically fatiguing to the rider, btw.
Try riding with earplugs?!?

I used to commute with both my stockers, and one 550 I had with a Mac 4into1.  I kinda drive by the tach in traffic (so I'm always within quick reach of the engine power band) rather than the engine sound.  I noticed that the bike made far more "thrashing" noises during the same commute with the MAC than with my stocker exhaust.  The actual speeds and tach readings were pretty much the same.

Cheers,

[chadbenson]

Hey TT, no pods or aftermarket exhaust for me. All stock on both ends but the bike is pretty loud due to the typical internal breakdown of the mufflers. I agree about the *sound* which I feel like contributes possibly to the frantic feeling. I'm looking into buying a pair of these:

http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=25567&store=Main&catId=&productId=p25567&leafCatId=&mmyId=9298 seeing I don't want to rejet with a 4 into 1 and can't afford $800 dollars for new 4 into 4's. Any experience with those? For awhile I used to ride with my musicians ear filters which allows you to hear all freq's but just 15 db softer. But after a week of that I went to just straight foam earplugs that cut about 30 db's out. I can't stand to ride without them, because all the car/road and bike noises tend to get to me after awhile. Riding with them makes me a much calmer rider.

[Bluegreen]

These bikes will cruise at 6500+ all day long, they only just start making hp after 5000. And your speedo could be way off! My first one was almost 20mph out at in 5th.

[TwoTired]

seeing I don't want to rejet with a 4 into 1 and can't afford $800 dollars for new 4 into 4's.

I don't think the mac 4 into 1 or the four into two systems require a carb rejet.  The mac 4 into 1 I had on a 75Cb550 didn't (after I put the stock air box back on).

Cheers,

[chadbenson]

seeing I don't want to rejet with a 4 into 1 and can't afford $800 dollars for new 4 into 4's.

I don't think the mac 4 into 1 or the four into two systems require a carb rejet.  The mac 4 into 1 I had on a 75Cb550 didn't (after I put the stock air box back on).

Cheers,

oh yeah? How did you feel about the ride quality/tuning of the motor? I do run a stock airbox but i've always been under the impression that if you go to a 4 into 1 you will need to rejet I'm thinking of lowering the bike some to help get more feet on the ground at stops. Would going to a 4 into 1 cause any clearance issues? Because you can get an entire 4 into 1 system for about the same price as you would pay for 4 into 2 mufflers.

[Duanob]

It's all preference but if I had my druthers I would do the 4 into 2 system because it would give you closer to stock look over the 4 into 1. It's too bad the stock mufflers can't be rebuilt because they have the best look. Maybe somebody has tried.

I think your problem is like this: You drive your car with the radio on all the time and you get used to it. Then you drive without the radio on one day and you think what's up with all the rattles, squeaks, and odd noises all of a sudden! They were always there but you just didn't hear them with the radio on. You said you rode with noise cancelling ear muffs then with regular plugs. Did the frantic noise start when you switched your ear plugs? Just curious.

[TwoTired]

oh yeah? How did you feel about the ride quality/tuning of the motor? I do run a stock airbox but i've always been under the impression that if you go to a 4 into 1 you will need to rejet

If you remove the baffles in the standard mac muffler to make it louder, you will need to rejet.
I ran a cheap four into two system (stock head pipes/ aftermarket mufflers for 10-15 years, no rejet, on the 74 Cb550.
As I said earlier, I reanimated a 75 CB550K that came with a Mac 4 into 1 with the baffles intact.  It had pod filters and ran sickly with the stock settings in the carbs.  I put on the stock air box with a Uni NU4055 air filter instead of the stock paper one.  It ran like all the other 550s I have, good power, good throttle response at all settings, decent economy  It got so windy at 95 that I backed off the throttle.  I expect it would have gone faster if I persisted.  It would cruise at 80 without complaint or issues, other than rider buffeting.

I'm thinking of lowering the bike some to help get more feet on the ground at stops. Would going to a 4 into 1 cause any clearance issues?

Not if you keep the bike straight up.     But, in turns, probably.  The springs compress in turns, bringing all the bike bits closer to the ground.   A 4 into 1 makes scraping in left turns more likely than in right turns.  But, if I recall correctly, the foot peg scrapes before the Mac 4 into 1 did.  I must warn you that the MAC 4 into1 is not a performance muffler system.  And, that it didn't work with the stock center stand, so the stand had to be removed.  This is a headache for routine maintenance like chain lubing. I added a pic of the bike below.

If you use the common rear lowering blocks, it changes the spring angle.  Doing so places more stress on the rear swing arm bushings and wears them out faster.  Then the bike wobbles down the highway as the rear wheel "hunts" side to side due to swing arm play.
I don't know if you can simply find shorter shocks, but if you do, make sure you get stiffer springs to reduce the "squat" during higher G loading turns.

Have you tried a lowered/narrowed seat to get your feet on the ground?

Cheers,

[chadbenson]

It's all preference but if I had my druthers I would do the 4 into 2 system because it would give you closer to stock look over the 4 into 1. It's too bad the stock mufflers can't be rebuilt because they have the best look. Maybe somebody has tried.

I think your problem is like this: You drive your car with the radio on all the time and you get used to it. Then you drive without the radio on one day and you think what's up with all the rattles, squeaks, and odd noises all of a sudden! They were always there but you just didn't hear them with the radio on. You said you rode with noise cancelling ear muffs then with regular plugs. Did the frantic noise start when you switched your ear plugs? Just curious.

As far as aftermarket exhaust goes I like the looks of the 4 into 2 better myself. Would be nice to have the 4 into 4's but not for $800 bucks! I have a '89 Jeep Cherokee which is about to turn 300,000 miles so hearing rattles and noises is nothing new to me, lol!! And I hardly ride with the radio on, but I do know what you mean. when I switched ear plugs I actually went to just straight foam ear plugs which cut all frequencys by 30 db. The plugs I used before were my musicians ear plugs which allow you to still hear all frequencys but at 15 db's softer. The "frantic" noise to me I suppose is really just ratty old stock exhaust. Like i've mentioned before I usually run 55mph at 5k rpms (from what my gauges tell me) and it definitely sounds like I SHOULD be hauling butt but am not going that fast at all. What really discouraged me the most was when I tried riding with a large group of my moto club members I was having to ride the bike as hard as it would accelarate to just keep up. Granted they all ride much larger CC bikes. From what other people have said about their 550's I just don't feel like mine performs on par with the norm. I'm making sure this winter that I go over it with a fine tooth comb.

[chadbenson]

Love that blue on your 550, TT! What a nice color! I think i'm going to stick with the stock headers and go with the 4 into 2's. Cleaner looking to me and they allow center stand retention  There is a place I've found who has a pair of 11.40" shorty shocks I'm looking at. My dad mentioned having the seat foam shaved down as well. I need to get it recovered soon anyways. Though I would really like the seat to remain as stock looking as possible. I'm a fairly short guy (5'5") and I feel like 1-1.5 inch drop in suspension would be pretty good. I wouldn't be able to flat foot but 2/3rds of both feet will make me happy  I actually have a extra pair of forks that I'm going to modify for lowering the front end. That way if it just rides like crap lowered I can always revert back to stock.

[dave500]

im only 5/4"ive dropped the front forks as far up as they can go just clearing the bars,gives a little faster turning maybe aswell,ive rigged up a square washer at the centre stand clamp that acts as a stopper in the retracted position. my hagon rear shocks are 310 mm,a touch over one foot,its a 73 500 with the standard seat foam,is the 550 a little taller generally than the 500?

[chadbenson]

my hagon rear shocks are 310 mm,a touch over one foot,its a 73 500 with the standard seat foam,is the 550 a little taller generally than the 500?

I don't think so, though I believe every bike is somewhat shorter or taller as far suspension and stuff (i.e. old worn out shocks and fork springs) I've got a buddy who has a 75 550k and his is shorter than mine soooo..... I need to measure mine but I believe stock 550's came with 13" shocks. 

[TwoTired]

750's had 13 inch shocks.  Cb550 had 12.5 inch shocks.  750 shocks are more widely available, soooo....
But, that is only part of the ride height issue.  The spring rates/length, preload setting, and bike loading also affect bike ride height.
750 shock units also have stiffer springs than the 550s due to bike and load weighting.  I you have 750 shocks, that's part of the problem.  The "performance" upgrades usually stiffen the springs, too.  (More is better salesmanship.)

Cheers,

[Duanob]

In other words, drink more beer! Get that beer belly rolling, add about 40 lbs and the back end of that bike will sag right down to a perfect height. Just check out most Harley riders, that's their secret.