After pondering on this for a few weeks, I verified it last night with my tank refill.. I believe my bike is running too rich.. I personally have 3 total shims, 105 main jets, removed resonators, and a K/N filter.. I got my worst fuel mileage ever with 40mpg on this last tank fill.. Riding back and forth to work, nothing changing. My plugs are suspect as well.. I personally am going to eat my words on previous threads and I am going to go back to 102 main jets.. I think the 105 jets are too rich for my specific bike.. After installing them, I have seen no personal improvement on performance. Just rich plugs and bad fuel mileage.. I may also decrease my shims to a total of 2 instead of 3. I will begin this tonight after I ride home.. After looking at Dave Dodge's shim kit and what it says, I believe he is right. Add 105 mains only for aftermarket exhaust.. Just my .02 worth, thought I would share..
Lance,
What you might do first before you pull the carbs is reduce your shims to 2 total, this can be done w/o removal of the carbs, I think 3 shims total is too much. I think your jets are fine, it's your shims, they come into play between 1/4 and 3/4 throttle for the most part.
The good part is to recognize this as you did. You have to go too rich and too lean to find your limits and the middle where it should be.
No words to be eaten, all of this is trial and error Lance even if you have the fancy equipment!
Thanks Terry, may try that.. Just don't know if removing 1 shim will cure it or not..
A couple of things to consider:
1. when tuning (especially fine tuning) make only 1 change at a time.
2. weather conditions have a strong effect on tuning and have to be considered when tuning to find a "balance".
Back in my sportbike days I used to re-jet often to match weather conditions. Of course I was more anal back then and had way more time on my hands. :roll:
I don't know much at all about shims or jets. :-? My bike normally gets 35-42 mpg depending on how I ride. Is this normal? I noticed that you were complaining about 40 mpg. I talked to a guy who rides a VTX 1300 and he said he gets 50mpg. I thought I got less because of the 4 cylinders.
Also, my bike has the original exhaust with the baffles removed. It was like this when I bought it. I heard that I would have a little more hp with the baffles in. Does anyone know if this is correct?
Fitzgerald, When I bought my bike it was completely stock.. Got 48-52 mpg constantly. When I changed the shims and added k/n filter I still got 45-50 mpg.. I cut the resonators out and added 105 main jets (102 is stock) and my mpg has dropped significantly to 40-45mpg. My plugs continue to stay wet as well. Therefor, I believe I am running rich. I don't remember what year model your bike is, but if it is a 3rd gen. I would suspect you may need carb work.. Seems to me your bike may not be getting the fuel mileage it could, or you may just ride it hard.. :lol: I'm not sure if your bike is loosing power due to removing baffles or resonators, if it is it shouldn't be significant I would think.. You may try some seafoam, everyone loves it here, and it helps keep your carbs clean.. I just went thru a can myself..
I have always averaged about 50 mpg (muffler mod only).
I had it tuned up last year, spark plugs changed, valves adjusted, radiator flushed, etc.
I don't know if the jets were changed when the resonators were removed. it seems your bike and mine have similar mpg though. I'll monitor my riding style and mpg. I consistantly get about 96-100 miles per tank before switching to reserve.
I went as far as changing the air filters but I don't have the time, space, or service manual to start tearing the bike apart any further than that.
Fitzgerald, remind us again what year your bike is...
97
Last week, my bike hit 92 miles and started to bog down.. Had to switch to reserve.. Not too happy. :mad: Usually get 105-115 before reserve.. and that's around town.. :sad:
Was that before or after the Seafoam? Do you run regular or premium gas? Would that make a difference?
Switch those jets then give us an update.
Allright guys, took 1 shim (1 shim only) off of each needle last night as requested.. Will give a follow-up after Bikes Blues & BBQ is over.. :-D Hope to put some significant mileage on the bike during the event.. :cool:
I believe a few of us are seeing a hit in gas mileage because of ethanol. A few years ago only the "cheapie" gas stations had ethanol blend. Now ethanol is ubiquitous.
Most of my Magna riding was before ethanol was unavoidable. When I first got my '99 I would occasionally hit 50+ mpg, but after getting used to her I settled down around 45 plus or minus. I may have dipped below 40 a few times, but that was not the norm.
Curtis
My '96 has Cobra pipes, K&N Air Filter, DRP-64550 Shim/Jet Kit installed as Greg instructs in http://www.magnaownersoftexas.com/tips.htm#A1.31
Austin does not have mandatory ethanol, and I avoid it when possible. My mileage varies from 45-52 mpg. Longer rides are typically nearer 50, while putzing around the back roads like I love to do is nearer 45. Once got 41 on a ride back from Marble Falls in a terrific headwind.
I am happy with this result, and with the bike's performance. :grin: :grin: :cool:
Lawrence, you are perfect with your set-up.. However, you have aftermarket exhaust.. I don't. Just have the resonators removed "muffler mod".. I will try this set-up for the weekend, but I think I may end up removing the 105 mains and replacing with 102 mains in the end.. I will keep monitoring plug color.. :grin:
Allright, here is the latest.. During BBB weekend I spent a lot of time on the magna.. Went on a poker run benefiting juvenile diabetes for the fayetteville firefighter association on friday. It was a 150 mile run up thru the pigtrail and the ozark mountains.. With my cousin riding on back I averaged 48 miles per gallon.. Pretty darn good I thought.. :lol:
Lance, if the plugs are the right color and you are satisfied with the performance, I would not change a thing. 48 mpg is a good result. Sounds to me like you have it right! :cool:
I refueled this morning with 87 miles on my tripometer. I put 2.48 gallons. That equals 35.08 miles per gallon. Not nearly as good as some of you posted.
I ride to work and back 12.5 miles each way. I usually go between 70 and 75 mph except through the constuction site (45mph).
What should I check that could be causing suck low MHG? I had the bike tuned up last year and I haven't rode much at all since then. Probably less than 1000 miles.
Any suggestions?
What year is your bike again? I only average between 35-40 per tank, closer to 35 more often. But I KNOW my carbs need to be synced (that spelling just does not look right) and I ride more like 70-85mph more often than I should.
I avg 38 MPH in normal riding on a 94. I think my 01 will do better though by the way it feels.....yep, Hootmon, it feels good baby all over!!!
I've got the 105 main jets (thanks Chad), 2 extra shims on each needle, and the K&N filter (everything else is stock), and I consistently get 42 mpg commuting back and forth to work on the expressway running 75 - 80 mph. When I'm out riding the back roads with my wife's bike club (60 mph max), I get about 48 mpg. I'm going to run it on the dyno at school this weekend and check the A/F mixture with an exhaust gas analyzer to see where it's at. I'm thinking it's a little rich, but I'll let you know after Sunday.
BA I think one shim removed would put you were you need to be. I would say your mains are OK.
Quote from: TLRam1 on October 02, 2008, 10:47:56 PM
I avg 38 MPH in normal riding on a 94. I think my 01 will do better though by the way it feels.....yep, Hootmon, it feels good baby all over!!!
You average 38 MPH on your 94 how fast do you ride your other ones? LOL
My bike is a 97 with the resonators removed. I'm unsure of anything concerning the carbs, jets, shims, etc. I have installed a K&N filter when I had it tuned up.
My '94 gets between 39.5 and 41.5 very consistantly..
K&N with 3/8" hole drilled in the tail plate of each exhaust. No shims (yet)... (waiting on Throttle cables- but that's another story...)
I have got as high as 49 on a nice 50 MPH ride and as low as 36 when riding 80/85 consistantly...
BA, I am very anxious to hear how your bike turns out after the analyzer and the numbers on HP.. My bike is identical to yours except for now I have 2 shims vs. 3 total on each needle. Keep us informed please!! :grin:
OK, here are my dyno results from earlier today...
Max Horsepower = 76.12 @ 8800 rpm
Max Torque = 45.46 @ 7800 rpm
Top speed achieved = 151 mph.
It was a fun day. The top modified bike run on our dyno was a turbocharged Hayabusa that put out 228 hp.
The closest stock Harley behind my bike was 70 hp, though there were three modified harleys that beat my Magna.
We did have one Valkrie that blew up at 131 hp.
Ok what did the analyzer say were you rich or lean and you have stock pipes right!!!
Sorry to say we were not able to use the gas sniffer on my bike. There were to many people waiting to run their bikes and not enough time, so only the HP and Torque run. It did backfire quite a bit comiong down from 150 mph.
Thanks BA for the results.. Pretty good for RWHP. I wonder what percentage we are loosing from the crank. 10%-30% ?? I don't know.. I am impressed! :grin: