Need more power

[scdmarx]

I'm learning to ask here first before tearing the bike apart, then asking here anyways. So I haven't done anything to address this yet.

The problem with my 83 Interstate is power in the higher gears. Well, maybe in all the gears, but most notable at higher speeds. Sometimes traffic requires me to twist the throttle and punch it into a safer position. A spot where I feel more comfortable. The problem seems to happen as I move past the 3,000ish rpm range and toward/through the 4,000ish rpm range. The power just sorta flattens out. Also notable when going up long grades at freeway speeds, amplified when riding 2 up, and-or against the wind. The power just flattens out. That's all she's got. 3/4 to wide open throttle, it just ain't gonna put out no more. I wouldn't say it bogs down, it just don't have anymore to give. I did look to see that the cables open the the throttle all the way (best I can tell?) and the air filter looks ok, but I haven't tried it with the air filter removed.
The bike seems to do ok for boulevard cruising. Taking into consideration the difference in the gearing between the 83 and my 82 Standard, I guess I really always did think the 83 was lacking in the "punch-power" department. In my mind I'm thinking it's lean in higher rpm. But that's just theory and I'm looking for experience to hold my hand.

So....any ideas you have to bounce around to get me started?

 

[mcgovern61]

If this is any help, if I punch it while at 3000 RPM on the highway in 5th (about 60 MPH) there is a slight bog until about 3800 RPM and them hang on for dear life....that bike is taking off!! :hi:

If I need to pass someone while in 5th gear (overdrive) I drop to 4th and punch it. In seconds I can be doing over 90 miles and hour or better (speedo stops at 80 MPH).

If I wind out 3rd gear at 3/4 throttle I will be burying the speedo even faster (even two up).

All of this just for a reference.

 

[Omega Man]

There is a steep grade over Mt Charleston, we call it "the hump to Parhump." If Jan is on board and I lose my momentum to a slow cager forget it, WOT gets us back to about 35-40mph tops(if we're lucky).

I did hit a crazy powerband spot in traffic dodging an idiot once...twas a little scary. It's never hit that spot since...and I'm not sure I ever want to find it again, I truly think the front wheel could have lifted off the pavement.

~O~

 

[slabghost]

Have you set the fuel mixtures and synchronized the carbs? Are the valves set? Is the vacuum advance responding properly?
Also. The float levels should be set. If they are a little low the fuel flow will be insufficient at higher rpm.

 

[joedrum]

id say there is some carb trouble and maybe advance in there too ...cause realy there is no bog with 1100s who carbs with fuelpump and vacume and mechanical avance working good that gives any bog at low rpm ...they tend to shut down at higher rpm at 7 grand or so normaly ...so ron id say its a combo thing going on to bog down low in the rpm ....absolutly more noticable on the 83 overdrive

 

[scdmarx]

I guess the easiest place to start is to verify the advance is working right. I just assumed at high rpm it would be maxed out anyways. But I suppose if it's faulty to begin with it ain't gonna be there at the top end either.

About checking float level, I think I remember seeing something about doing that while still on the bike. Anyone got a link to that info? I wish I could verify fuel pressure, but I haven't had a gauge that goes that low in years.
Carbs have been recently synced and valves adjusted. This problem was there long before that and it still didn't help.
Mixture adjustment - that's with the 90 degree screwdriver, right? Haven't done that.

Maybe I need a NOS system? :shock: :smilie_happy: :smilie_happy: :smilie_happy:

 

[slabghost]

Could copy Joe's angry dresser with early carbs and cams.

 

[dan filipi]

Ron, I would first have a look at the spark plugs. They should all be even tan with no sooty build up.

Over rich as well as over lean can cause power drop offs.
My #2 carb was flooding under power, felt much like a lack of gas.

While plugs are out check compression. No sense chasing other possibilities if there's low compression.

The ignition is a major weak point on these bikes. They need every bit a good connection on all primary and secondary wires.
Each plug wire can be trimmed at the end a 1/4" then screwed back on the cap.
While those are off check the brass pin that stabs the wire is shiny clean.
If your running resistor plugs, replace the resistor in the plug caps with a solid piece of 8 gauge copper wire or something similar. Having the resistor in place will reduce spark.

In overdrive mine is a bit doggy but once in 4th I have everything I need.
I'd be curious to try this grade ~O~ mentioned.
We have one called the "Grapevine" which you know about.
2 up @ 325 lbs and bags loaded with over night stuff I can pull it in 5th ONLY if I hit the bottom at 70-75 mph and nobody slows me down but once down into 4th she's happy pulling us up at 5-6k rpm.

 

[Anonymous]

hey Scd if you need more power buy my scooter!! A buddy and I were out for a ride (we have intercoms) we just made a turn onto a quiet back country road, he was in front and excellerating as he said LETS GO!!! I passed him in what seamed a few hundred feet, next thing I knew (seconds later) I was doing bettern a buck 60 (100mph) as i was shifting into 5th (6 gears in total) I was / am too chicken to open her up full this was about 3/4 throttle and never got close to the redline. Scarey how fast this thing is - Guiness book shows it the fastest production bike built at that time.

 

[toytender01]

I was having some problrm with bogging down, that kept getting worse. Changer the fule filter and cured the problem. the output side of the filter had collapsed. (kinda like someone had used a crimper on it) Would bogg down at crusing speed and on hills. Just a thought

 

[scdmarx]

I was having some problrm with bogging down, that kept getting worse. Changer the fule filter and cured the problem. the output side of the filter had collapsed. (kinda like someone had used a crimper on it) Would bogg down at crusing speed and on hills. Just a thought

Filter is a year old. I think It's time to change it anyways. :builder: Thanx.

 

[KYWinger]

:headscratch: This has got me wondering....are there any things we can do to up the power on these? Mine runs great (Pistol Pete did a card job w/Randak's kit) but any EXTRA power would be a plus- especially riding 2 up.

I'm guessing that custom cams and high compression pistons would be $$$$$$ if they are even available at all.

I don't want to buy a GL1800.......just have my ol' 1100 run like one! LMAO

thanks guys :thanks:

 

[joedrum]

early cams and carbs from 75-77 10002 will bump the power of the 1100 ...early 75-77 cams alone with stock 1100 carbs bumps the power good also ......my 83 is a dressed interstate ...its runs faster than 1500s and ithink it runs just as good as an 1800 ....ive only mess sround with one 1800 while riding ..he did seem to have any more power than i had.....

 

[KYWinger]

:clapping: Thanks for the tip, Joe - since I've invested a fair amount in getting the carbs spot on, I might search out early cams....

???????Question: Does anyone know a resource where I can go and compare cam specs (lift, overlap, separation, etc.)????

:good: Thanks, guys!

 

[AApple]

Need more Power...

Perhaps your dylithium crystals need replenishing?

"Aye...she con tae mooch more, Cap-n."

:hihihi:

 

[scdmarx]

Quick, somebody hand me a piece of scotch tape! :builder:

 

[joedrum]

:hihihi: :mrgreen: thats good ron

 

[bronzestarvue]

Nah, I think he needs to resolder his flux capacitor...

 

[ekvh]

I'll bet most people with the early 75-77's don't know how fast they are because they don't want to let them rev. It took me five years before it sunk in where the power band is on them. If you want a kick, take your gl1000 up to 9500 and hit second gear......it hauls pretty good. Hit third gear and you have to back off unless you're sure there are no license removers around. Too bad someone couldn't figure a way to get the gearing lower for take off. The 1100's power bands are lower rpm.

 

[joedrum]

the earlycams on 75-77 basicly have longer duration ...than other olwing cams and the overlap is 5degrees each way for a total of 10 degrees ...all oldwing cams the overlap the same