Thots on 24 Top Gear for Attak\LTX

[steiner]

My 2007 Attak has the stock 23 top gear. I do have a 24 gear sitting on the shelf. What would I gain or lose switching to the 24 like the 121 Apex have? Running an Ulmer Stage 2 kit with about 10k miles on it now. Primary cut for overdrive. ( I saw no gains with this mod) Spinning a 1.2 Ice Attack track.
Did run a ram air lid mod and full Excel exhaust for awhile. No programmers. Sled had no top mph gains nor fuel mileage changes compared to a stock Attak. Just gained a lot of more db pollution.
My sled has always used my fuel than a buddy's stock '06 Attak. I was always a liter or 2 more. Always chalked that up as to leading the group. Now another buddy just bought a 2007 Attak. Its all stock and even is the same color and graphics. We did a short ride of 40ish miles or so the other day. I used 5l more than he did. Not cool. Im thinking at my current fuel consumption I will be looking for gas stations before the Nytros do.
Thats what got me thinking of switching to a 24 gear. Or should I spend some money in new clutching gear?

 

[Macheater]

I would expect a 24t gear to give only marginal improvement in fuel mileage. In comparing your sled with the others, there's a number of things to compare. Obviously mods, riding style, and on & on. Your mileage seems to be substantially worse than your riding buds. Do their sleds have a fuel programmer setup for better economy? Are you frequently pinning the throttle?

It sounds as if your goal at this point is better mileage. Unfortunately, there aren't a lot of ways to achieve it. Restraining your right thumb remains the best way. Aside from that, a fuel controller that leans out the part throttle and cruise conditions, and the aforementioned gearing change. A clutch that spins at a lower rpm would also help.

I would think that an Apex setup for better mileage and ridden accordingly could achieve a 15-20% improvement.

I went with a 23t gear on my GT, and am getting ready to switch back to the 24t. But not for mileage reasons. I haven't had that many opportunities to compare my mileage to other similar sleds but, when I did, it seemed on par or better than them. I was about the same as a Doo 800 E-tec Renegade.

I too have an OD primary but, did it for speed reasons, not mileage. I wouldn't expect that to help mileage either.

Check any sources of friction or drag. Everything seem to be spinning freely? Bogie wheel bearings and the like.

 

[74Nitro]

Put an O2 sensor in the exhaust and monitor the readings. Make adjustments from there with a programmer.

 

[Macheater]

BTW, just as a point of reference. When ridden from a full tank, my low fuel light usually comes on around the 120-125 mile mark(193-201km). I have gotten as much as 143 miles (230km) out of a tank of gas, but that was REALLY pushing it, as I don't carry spare fuel. So I'm not able to run it dry to see just how far I can actually go.

That was with all the mods listed in my sig. Just recently I've started to fine tune the low rpm cruise for better mileage. And going back to the 24t, I would expect to improve on those numbers just a bit.

 

[Pete_man26]

I went from 23,22,21 for years, in the past few years after lots of testing I found in a 500ft snowdrag the 24 was the fastest on the timer, however this was on a prestine track with proper clutching, went to a race that had soft snow and racing my buddys attack with a 23 he would drive away, mine was a dog, I couldn't pull the R's and didn't have time to reclutch. I've went back to the 23 and it seems to be all around more consistent. As for the lake, the best MPH i've seen came with the 23 in it.

my 2 cents, leave it with the 23. added some wheels to the suspension if you havent already. Check the CO calibration thru the cluster, I don't remember what the stock setting is, I think 00 and it goes up in increments of 10. Maybe lay off the lever a little? If your anything like me when you see a nice straight stretch you squeeze it, that power is instant and pulls no matter what speed but drinks the fuel!

 

[Stubbs]

Are your buddies running stock clutching? I’d bet your cruising RPM’s are several hundred higher than your buddies due to the Ulmer clutching and that’s the cause of the MPG difference. Been there, done that.

 

[steiner]

BTW, just as a point of reference. When ridden from a full tank, my low fuel light usually comes on around the 120-125 mile mark(193-201km). I have gotten as much as 143 miles (230km) out of a tank of gas, but that was REALLY pushing it, as I don't carry spare fuel. So I'm not able to run it dry to see just how far I can actually go.

That was with all the mods listed in my sig. Just recently I've started to fine tune the low rpm cruise for better mileage. And going back to the 24t, I would expect to improve on those numbers just a bit.

First tank of fuel this year my light came on at 80 miles. Very warm temps and very loose snow. No trail riding, just in the ungroomed ditches. Lots of fun. Didn't expect that tank to last long.
Next tank the temps where still warm but cruising on the rivers and canals. Buddies stock stock Attak took 5l less fuel on that 40 mile run. Yes the fun flipper was used, a lot.
This weekend out again with the same group. Put on 50 miles and now sitting at half a tank. We did not do a fuel stop so I don't know how we did on fuel consumption.
On the TY rides over the years I casually check my fuel consumption against the other 4-6 Apex in the group. The stock Exup sleds always are better by atleast 5l on a longer run. the non stock Exup will be closer to 2-3l better than me. Again, I am leading the group so I expect to use more fuel but on these rides the fun flipper is relaxed.
My fuel light will usually come on at around 95-100 miles and have gone as far as 120 miles.
My track spins freely. It will even creep at idle when up on the stand. My skid comes out once a year and all bearings are cleaned and greased. Same goes for the jackshaft and driveshaft bearings. Had a dealer open the primary and all was good in there. Had it cut for overdrive while they had it apart. I know its not the motor or the valves needing adjustment because this is the second motor in the chassis. Current motor has 35oo miles on it. Original motor had 16k miles on it. Both motors are acting the same. Same top speed and seemingly the same fuel mileage.
Thus I am looking at gearing or clutching and the more I read and type I am thinking clutching. Maybe I should bolt on my Yamacharger and Excel full exhaust system. I know anther buddy of mine had a'06 Apex with the Yamacharger, Excel exhaust, Schmidt Bros. clutching and overdrive. We were about the same at the pumps. He just had more fun factor than I did.

 

[Macheater]

Pete brought up a good point. Check your CO settings. They could be on the rich side of the adjustment.

ALL of my riding is trail with zero off trail riding.

Off trail in warm mushy conditions is definitely gonna use more fuel.

The 2nd gen Apex's are setup much leaner from the factory. I would expect them to be better on mileage.

 

[Pete_man26]

Worst case, throw a set of stock weights and springs for one ride and see if there is a change in fuel consumption. easy to do and change back if it made no difference.

like stubby said, you are most likely reving higher then your buds but going the same speed. Could lead to additional fuel consumption.

 

[Stubbs]

Pete brought up a good point. Check your CO settings. They could be on the rich side of the adjustment.

ALL of my riding is trail with zero off trail riding.

Off trail in warm mushy conditions is definitely gonna use more fuel.

The 2nd gen Apex's are setup much leaner from the factory. I would expect them to be better on mileage.

Stock vs stock I found a consistent 8-10% difference in fuel mileage between the first and second gen. Apes when ridden side by side.