[woodchucks800]

Well guys I decided to start a thread in the cruiser's forum for this very topic since we've got 2 or 3 threads around this site talking about the same thing. So now with the topic. As I mention earlier I had a tach on my 800 so I decided to get some hard number's for everyone so were no guessing . First I went out at lunch an changed the 18 tooth back to the original 17 tooth an I'll start from there. 17/42 ratio I've got 3750 rpm @ 65 mph., 4250 rpm @75 mph.,[email protected] 85 mph. Now with the 18/42 I've got 3500 rpm @ 65 mph.,4000 rpm @ 75 mph., an 4500 rpm @ 85mph. So that tell's us the 18 tooth front sprocket drop's the rpm's 250 well worth it. when I change out the rear to a 40 tooth I'll add those number's to this thread. By the way< Here's a couple of other number's we can talk about . The rev limiter kick's in about 8200 rpm. from the factory. So I hit the rev. limiter at 72 mph. in 2nd gear with the 17/42 ratio. With the 18/42 I hit the rev.limiter at 80 mph in 2nd gear. The rev. limiter is our friend<BG>

 

[bikeaholic]

re

great job wood chuck 8)

i posted your info in the FAQ forum for reference-hope thats ok :wink:

 

[800AJAY]

Thanks for the test results WC. My guess would be another 150-175 with the 40T.

 

[Slicks]

Excellent WoodChuck.

** EDIT - Chart added using numbers above plus testing from other posters **

I'm very curious to see your figures for 18/40. As I put in another post, my biggest dislike of the 18/42 setup is cruising back roads at 48 mph (I would say 50mph but after following people for the past couple of months, I've noticed that they keep the speedo juuuust under 50mph. I know because I can shift into 5th at 50 and their speed just won't let me).

Using your numbers as a reference, with the stock setup (17/42) I'm guessing I used to run about 2800 - 3000 rpm in 5th gear. That was the "sweet spot" in my opinion. I could cruise that speed all day down back roads. Now that I've switched to 18/42, I'm running a higher rpm in 4th than I'd like to now at 48mph.

Is there any chance I could talk you into posting the rpms of 48mph in 4th gear with 18/42 and 18/40?

I'd be grateful.

 

[woodchucks800]

That's ok Biko wasn't sure which area of the site would get the most view's. Like I said when I get the 40 tooth I'll add some number's over in the FAQ site. If I can if not I'll post them in this thread. Jay that's what I'm thinking also. I may find some 16/46 spockets for when someone starts talkin smack. I'll just tell them I'll be back in about an hour, then we'll see what happens.(lol ) I can tell the difference with the 17 back on the front it ,with the 16/46 it will definitely have a good take off at the light.<G> Won't have much up top though, but who care's I'll be at the next light by then.

 

[woodchucks800]

Slicks I'll get some number's for ya , no problem , but you better stay back in PA. You'll get run over out here at 48mph. (lol) The reason I'm kiddin with ya is because all our back roads are posted 70mph. Hell Montana didn't even have a posted speed limit until about 5 yr's. ago. The only reason there posted now is because the feds. threaten to stop the federal road money.

 

[bikeaholic]

re

remember to allow for speedo error - they are all off somewhat

 

[Slicks]

Thanks WoodChuck. 70mph!!! Man, that's not putting in my book. Anytime I do 70 off of the highway, I'm chancin a stiff fine.

 

[woodchucks800]

Bikeaholic I forgot to mention that earlier. The speeds an rpm's are what the speedo endicated . I think from what I've been reading the 800's are about 10% high?

 

[PickYourPockets]

Thank you for all your work and expertise on this subject. You are gentlemen and scholars.

16/46 WC? You'll be shifting before you get out of the first crosswalk. Of course, you'll also get there very quickly.
:wink:

Now, if you'll excuse me, I need to place a call to SS.

 

[woodchucks800]

Slicks, Here's the number's you were wanting, At 48 mph in fourth gear with the 18/42 ,the rpm's are at 2900. With the 18/40 at 48 mph the rpm's are at 2700. WC

 

[woodchucks800]

Here's the number's for the 18/40 sprocket set up [email protected]'s.At [email protected] 3800rpm's. At [email protected]'s. I definitely like the 40 tooth on the rear. If you thought the 18 tooth on the front made you feel like you had an overdrive then you'll really like this set up. Kept finding myself in fourth at 65 or 70. Didn't notice much difference taking off from a dead stop compared to the 42 tooth. I can tell a difference between the 17/42 an the 18/40 taking off, but thats only because I've been changing the gears every hour! For the type of riding I do out here , I give the 18/40 two thumbs up!! I hit the rev limiter at 84mph in 2nd gear. One other note the 18/42 at 3500 rpm's in 5th gear was at 65mph. The 18/40 at 3500 rpm's was at 69 mph. It did the same increase thru all the number's so at least it seem's to be consistent.

 

[bikeaholic]

re

woodchuck - any real difference from 0-60 from a dig that you can feel?

 

[Slicks]

Thanks WoodChuck. I'm gonna have to chew on that for a while cause something ain't figurin....

Since I don't have a tach, I'm having match my memory of what my bike sounded and felt like at certain speeds and match it to your numbers. I remember with my stock setup of 17/42 that at 48mph, my motor was at the lowest rpm possible while still having sufficent torque. At 45 mph, it had no balls at all because the rpm was too low. According to your 17/42 figures, I worked it out that I was spinning 2900 rpm at 48mph in 5th gear. This would lead me to believe that 2900 rpm is the "sweet spot".

After changing to an 18/42, I've already noted in conversations with people that 53mph in 5th is now my "sweet spot" as it feels like what 48mph used to feel like. By working with your 18/42 figures, 53 mph equates to 2900 rpm. Again, 2900 rpm seems to be the sweet spot.

What's confusing is that riding 48mph in 4th gear with an 18/42 sounds winy and over-revved and your testing just revealed that I'm running 2900 rpm in 4th at 48mph. ????????

2900 rpm is 2900 rpm regardless of whether you're in 4th or 5th gear. If I had to match rpms and speeds by guessing, I would say that 53mph in 5th feels/sounds the same as 41 or 42 mph in 4th, not 48 mph. :?

This is all personal babble because the long and short of it is, if I didn't have Hard Krome Big Straights with their high-pitched bark, I wouldn't be quibbling over a few mph/rpm. I currently cruise at 50 mph in 5th (2750 rpm) just so it'll sound good and it feels like I have very little power available at that rpm.

Anyway, thanks for the numbers WoodChuck!

 

[Slicks]

Here's a condensed version of WoodChuck's numbers:

* 1st number = number of teeth on front sprocket
* 2nd number = number of teeth on back sprocket

17/42 - STOCK

55 mph - 3250 rpm
65 mph - 3750 rpm
75 mph - 4250 rpm
85 mph - 4750 rpm

18/42 (changing front sprocket)

55 mph - 3000 rpm
65 mph - 3500 rpm
75 mph - 4000 rpm
85 mph - 4500 rpm

18/40 (changing front and rear sprocket)

55 mph - 2800 rpm
65 mph - 3300 rpm
75 mph - 3800 rpm
85 mph - 4300rpm

 

[woodchucks800]

Bikeaholic--0 to 15 I notice a little slower than the 17/42, not much different compared to the 18/42. You can feel the gears are stretched out a bit between shifts, the speedo an tach show that on the 3500 rpm 65 to 69 mph. The roll on from 15mph on up feels the same especially with the gears stretched out. If I wasn't riding so much 65 an above , the 18/42 would be fine. A week from now won't remember the feel of the 17/42 . Kinda forgot about it over the last year and a half since I went to the 18 front.

 

[woodchucks800]

Slicks-Don't know what to tell you ? Just read them as I saw them. Thanks for the chart.

 

[800AJAY]

I received the 18T sprocket today and will be putting it on tomorrow. Will let you know the feeling of the revs I get from the change.

 

[800AJAY]

Well, the 18T sprocket I ordered doesn't fit the stock chain. It's too narrow and requires a 520 chain. Stock is 530. The 18T is not available in the stock chain size according to the Kawi dealer I ordered the sprocket from. The solution is to go to a 39 or 38T sprocket on the rear to get the same effect as an 18/40. Anyone else run into this? Surprised I didn't hear anything about this problem.

 

[woodchucks800]

Jay First don't use the 520 sprocket ,if kawasaki wanted a 520 on the 800 they would have put one on it! Next swapping the rear to match the 520 in the front will also require a new 520 chain. Your spending more than the 20 bucks you planed on now! Go back to your dealer an tell him you want your money back . Then tell him to spend a little time looking for a 18 tooth 530. He should be able to buy from www.spocketspecialists.com also. My dealer here in Bozeman can an did for 13 bucks no shipping plus 10% discount on next order. If you decide to get a 40 tooth for the back, JT sprockets is the only one making them right now 36 bucks. The dealer can order them .Also sprocketspecialists doesn't carry a 40 tooth anymore. My dealer told me jtsprocket only made the 40 in the 520 size. NOT! Had to look the number up myself an told him to order it. If you still have a problem finding an 18 tooth I've got an extra still in the package I'll sell ya. Call beartooth an have them order you one an tell them Team Bozeman will sell you one for 13 bucks. That's some of there competion. HAHA( probally charge shipping though) Dealer's can be fun sometimes. They love when I come in the shop, part number's in hand. I like the owner an shop manager plus the discount that's why I stick around.