Stock engine performance

[BIKERTUCKER]

Just purchased a 1982 GS1100L, Guess that makes it an eight valve engine. My question is, what should stock performance be on the GS1100L
engine? Searches so far give great info on how to improve beyond stock
performance, no luck on stock performance. Compression between 145
and 155psi. Carb Sync is on the mark. It starts almost instantly on cold mornings at full choke, idles smoothly and on the road begins to surge ahead nicely beginning around 4800 rpm. It's a bit of a cold blooded beast, needs to go down the road a few miles before choke can be opened and engine stops missing. Also performance is a bit bland untill around 4800 rpm, at that point it will set you back in the seat and gets your attention focused on the road. Are these items above normal or not.
Any replies are a welcome. Not wanting to spend time working on something that is just a nature of the machine.

Thanks
Tim

 

[posplayr]

compression limits and typical are listed in the OEM manual. See Bikecliff's website for your model.

 

[Larry D]

Here's Cliff's site. A ton of info there.

http://members.dslextreme.com/users/bikecliff/

 

[Nessism]

Sounds like normal performance. The cooled blooded nature of the bike can be improved by doing a carb freshening with new O-rings, and shimming the needles a smig. Tons of info on this in the archives.

 

[twr1776]

Today, 02:09 PM Nessism Sounds like normal performance. The cooled blooded nature of the bike can be improved by doing a carb freshening with new O-rings, and shimming the needles a smig. Tons of info on this in the archives.

I agree with Ed on the carb work and what do the plugs look like? Do you have any intake or exhaust side air leaks? If you have a stock airbox the intake leaks can also rob some power and should be fixed to avoid any damage to the motor for running lean.

The above 4800 RPM mark is about right for when the motor really starts to pull although it is no slouch below it IMHO. The GS two valves like to spin to maximize torque. If it seems to take a long time for yours to warm up I would suspect you have dirty carbs or some possible air leaks.

 

[850 Combat]

It should pull hard before 4800 RPM, although it should be getting darned meaty around there. I think you might be a bit lean, either with air leaks or carb issues, more than likely a combination.

I have an old road test chart of a 1000G in my albums. It ran 12.2 in the quarter. The 1100 is geared a tad taller, but should have a bit more pep.

I have not found a test of one, but guess it would have tested at 12 flat give or take.

 

[doctorgonzo]

That sounds a little weak on the low end, but not that much. These bikes don't really start to pull well until about 4000. The real power is in the 6000 to 10,000 range.

 

[BIKERTUCKER]

Thanks to all. Just what I was looking for. I'll move forward in checking air leaks and pull the carbs next chance I get. Also thanks for direct links for needed info.

 

[BIKERTUCKER]

Removed air box and carb's last nite. Found O - Ring's between intake boot and head had converted into flat piecies of crumbly plastic. Local shop had new ones in stock. It's forecasted to be a nasty weekend. Will have to delay test ride till next week. The engine now in the bike had not been running for some time so I want to run it for a while and then check the spark plugs for color indication. I've ridden it enough to burn a tank of gas, but it's also sat at idle a good number of times while preforming other checks. Will also check carb sync once more before test ride. Thanks again for some direction on my new adventure.

 

[twr1776]

Since your boot o-rings are bad you might also want to go ahead and get the carb o-ring kit from http://www.cycleorings.com/ and go through the carbs and clean them while you have them off the bike. There is a small o-ring on the air mixture screws that will make the carbs VERY hard to adjust properly unless replaced.

 

[BIKERTUCKER]

Thanks for the carb o-ring kit supplier.

 

[jimfj]

i Have the 1100G. Same motor. I want to echo Nessism, Shim the needles on your carbs. You will invest about $10.00 between a set of long thin needle nose pliers and the washers. The difference in feel at startup and in the low to midrange is like unlockin the cage and letting the beast out. Mine did the same thing yours is doing. Full cleaning and o ring replacement and shim.......WOW.

Good luck.


Jim

 

[BIKERTUCKER]

Thanks for the suggestion to shim the carb needles Jim. I'll do just that in the future.But for now need one other item before carb work.Thought airbox
came off and went on too easy. After searching, of course it's missing the
air box snorkle. So I'll put I shout out here and in wanted section for
Lower Rear Airbox Snorkle for a 1982 GS1100L or any other that will fit.

Thanks

Tim

 

[BIKERTUCKER]

Jim:

What thickness of shim did you end up with on needle?

Tim

 

[Nessism]

Thanks for the suggestion to shim the carb needles Jim. I'll do just that in the future.But for now need one other item before carb work.Thought airbox
came off and went on too easy. After searching, of course it's missing the
air box snorkle. So I'll put I shout out here and in wanted section for
Lower Rear Airbox Snorkle for a 1982 GS1100L or any other that will fit.

Thanks

Tim

I have an airbox from a GS1000GL. Check your PM for photos.

 

[BIKERTUCKER]

Ed: Appreciate nudge on PM. That option was new to me. Replied this am.
Sounds like a good deal.


Tim

 

[gggGary]

As long as you are this far go whole hog and clean out the carbs, either do it or say duh-oh in a week or so. Pull the float valves, There are O-rings and small screens up above the float valve bodies, pull em, clean em, and spray out the fuel passages. put in the float valve o-rings and pull the rubber plugs and pilot jets. The pilot jets are the favorite hiding place for little pieces of crud. This group is big on soaking in berrymans but I have had great success with spray carb cleaner. I figure on two cans to do a rack. I just got my barn fresh GS1100EZ rack on the bench tonight and you can bet I will do all these items.

 

[BIKERTUCKER]

I did all the cleaning last nite. Did find a good amount of crud. Need to order O - ring kit yet. Filter screens under fuel valves were clean. As if they and only they were removed and cleaned. I too spray clean carbs,due to some have felt seals between carb and control shafts that get destroyed if dipped leading to air leaks and lean running. I do use Berryman B-12 spray,great stuff.

 

[BIKERTUCKER]

Ed: I'll take the air box. same part#'s on mine. Let me know the how's and when.


Thanks

Tim

 

[BIKERTUCKER]

While waiting for my new air box to arrive,decided to play with shimming
the carb needles. Went the nylon washer from the hardware store route. Found one previous message where the needle was raised .032 in, and owner thought he could have gone twice that amount. Made that my starting point. Raised the needle .064in or (1.63mm).At first I thought I had gone too far engine seemed like it was bogging down at higher RPM because the Large surge of power around 4800rpm seemed reduced. But once on the open road found it pulled much better from start till the 4800 rpm point. And since it was preforming better below 4800 rpm the kick did not seem as great from that point on but the speedo needle kept moving quickly till it was pegged. So it did make a nice performance improvement in all the right places. Plus now when given throttle at lower rpm it pops forward instead of making more noise but struggling to move as it did before. Was tempted to remove the last remaining washer but decided to see how plugs look after I install the new air box with snorkel. Right now after a 18 mile ride, plugs had a white/tan color to them.