Newbie Tuning Help

[mtarter]

Howdy, long time lurker, first time poster.

Have a 2015 Ruckus with 1000 miles. I am about 220lb and was doing about 37 or so beforehand down a good hill. Hit 40 once on a massive hill. Have ridden a similar mileage stock ruckus and topped out around 42 pretty consistently.

Anyways this Ruckus was running pretty lousy bogging sporadically until it got to WOT, and seemed noisy compared to the similar mileage Ruckus. I replaced fuel pump, fuel filter, and pilot jet with OEM parts, put in fresh gas and did an oil change with Motul scooter 10W30. Once the bog seemed gone, I added an NGK spark wire and iridium plug as well as a UNI filter. It seemed to run good, and I really should have took it out for a top speed run at this point but CVT was still kind of noisy so I kept going and added Dr Pulley 5.5g 16x13 sliders to replace my stock rollers that were a little bit flat, and I also replaced my seemingly unworn stock belt with a Gates Powerlink. Now I’m not totally sure any of this was really necessary besides the pilot jet and maybe rollers. But I like the idea of keeping it relatively stock and experimenting with tasteful mods for a little extra oomph that won’t impact reliability.

I think replacing the rollers solved my noise concern (pending side by side comparison with similar Ruck) Problem is, now I get on the road and seem to be bouncing off the rev limiter in no time, which has me topping out around 29, It feels like I hit the rev limiter almost immediately on most downhills but also seem to be getting there on longer uphill sections too. Im assuming it’s the rev limiter because on downhills the bike noticeably slows at this point, and on flat ground it seems to very subtly slow and then jump forward a hair then slow again - creating this very slight “bouncing” feeling.

So all that being said I am looking for some insight on why I can’t get up to speed anymore. I feel like the accel is a bit quicker especially mid-range and engine feels a bit more responsive but Id really like to be able to hit 40 or so. Are my 5.5G sliders too light/heavy? Should I get a CDI so the scooter can just keep revving past the limiter? Do I just need to wait for my new belt to break in? Is there some common ruckus issue I didn’t check or assembly mistake I might have made (I’m pretty green here but but followed Mitch’s CVT guide on Youtube) I also ordered 7g (stock weight I think) Dr Pulley Round Rollers to try and mimic the stock rollers, and can run those and/or my stock belt too once they arrive. But ideally if the sliders offer any acceleration and reliability gain without impacting top speed like this id love to use them/find the right size.

[Baizy]

Thanks for lurking and learning on the forum! I hate to say it but I think you've thrown too many parts at the problem. If you're bouncing off the limiter at 29MPH and the ruck sounds like it's revved to the limit it's something slipping.

The gates powerlink is a tougher belt so it takes longer to break in and longer to warm up for the ride, leading to slippage. The clutch could also be worn out in the rear and not grabbing all that well, they are not very good in the first place so maintenance is pretty important.

You've likely done this already for tuning but I'll explain anyway. Slap some sharpie lines on your variator from the bushing to the edge then go for an extended top speed ride. If the sharpie is worn off close to the edge and you're going slow it's clutch or belt slip. If it's not worn close to the edge it's something with the variator or potentially the clutch pulley is binding, too light a weight would cause that as well.

You can also get a 1 wire lawnmower tach to confirm the engines redlining. 8800 RPM is the max for 2006+ rucks so watch where it is when you've hit peak speed. Hope this helped!

[mtarter]

Thanks Baizy, I can see you actively responding to a ton of threads here recently, and even today! Appreciate people like you keeping these threads active and full of useful information, and especially appreciate the fast late night response here. I have not actually done the sharpie thing, will try that tomorrow. And will also grab a tach to confirm RPM.

[mtarter]

Ok so I ran the sharpie test and after 2 miles of mostly WOT yielding a consistent 29mph across uphill/downhill/flat I still have ~3/4” of marker left untouched. Pretty sure clutch and variator are torqued correctly belt seems to be moving as it should. Have a tachometer arriving tomorrow and stock-weighted rollers should be here this week. Anything else worth checking besides RPM while I wait for the rolllers arrive?

[Baizy]

May 3, 2021 1:41:32 GMT -5 mtarter said:

Ok so I ran the sharpie test and after 2 miles of mostly WOT yielding a consistent 29mph across uphill/downhill/flat I still have ~3/4” of marker left untouched. Pretty sure clutch and variator are torqued correctly belt seems to be moving as it should. Have a tachometer arriving tomorrow and stock-weighted rollers should be here this week. Anything else worth checking besides RPM while I wait for the rolllers arrive?

You have got way too much sharpie left! Normally you end up with a 1/4" on a stock ruck, so you have got something bad going on. Best advice I can give you here is to pull your variator off again and check that it slides freely on the bushing and that the bushing isn't damaged. Another thing would be to try and open the clutch pulley all the way by getting the belt as deep as you can. Unless you forgot to put half your weights in or the sliders are in backwards you really should be wearing off more sharpie.

[Baizy]

May 2, 2021 23:27:25 GMT -5 mtarter said:

Thanks Baizy, I can see you actively responding to a ton of threads here recently, and even today! Appreciate people like you keeping these threads active and full of useful information, and especially appreciate the fast late night response here. I have not actually done the sharpie thing, will try that tomorrow. And will also grab a tach to confirm RPM.

Thanks for the compliment! Doing my best to help other Rucksters going forward and at speed! Glad I was able to teach you something with the sharpie method of tuning. It really is great for both troubleshooting and tuning. Paired with a tach its the best budget tuning measure out there. If you ever feel like you have money burning a hole in your pocket the Koso Mini AFR kit is great for dialing in your jetting.

[mtarter]

Ok so my 7g Dr. Pulley rollers came in today, just threw them on and was able to get up to 41/42, with maybe 1/4 in or so left of sharpie on the variator, and it did not feel like I hit the rev limiter. I did grab the tach but will probably install that to confirm later this weekend... unless there’s some easy way to get at the coil without taking the floorboard off. I’m assuming I’ll want to know the RPM I’m topping out at now before deciding if I should tune further? I’m generally satisfied now, but would love to guarantee a race win over the rival stock ruckus I mentioned in my OP.

Not sure if this is the right place to ask, but I also am noticing a slight bit of hesitation from 10mph-20 almost feels like a stutter or slip from the transmission while it’s opening up, accel feels consistent everywhere else, end engine doesn’t seem to be bogging or anything like that;. I’m assuming this could either be due to the new Kevlar belt or potentially a worn clutch? But not really sure. Any insight here would be great too.

[mtarter]

Also that AFR kit is awesome never heard of that, but makes sense

[Baizy]

Hey mtarter glad to hear you're back up to speed and working towards that big win. I have never run a floorboard myself but I worked on a buddies once and they have an access dor for the spark plug so you could just do a real quick install and checkup, but to actually install it and run the wires cleanly you'll have to pull the floorboards, battery box, and fuel tank. Your low end slip/shudder is likely 100% your kevlar belts fault. I recommend OEM even though they wear down faster because they grip really well!

On a side note I'm glad you looked into the Koso Mini AFR. They really are neat little gadgets!

[mtarter]

Cool, I thought I had to install the tach wire to the coil for it to work, but worked just fine wrapping it around the spark wire itself. With proper tire pressure I think I’m now definitely catching 42, maybe 43 around 8700RPM down a short steep hill that follows a long flat stretch. On flatter ground cruising RPM seems to be closer to 37 at 7300/7400 RPM. And that’s good advice on the belt, I’m gonna put some mileage on this one and see if it gets stickier as it breaks in, if not I’ll swap back to stock. Also fwiw realized my rear brake was a little too tight causing some friction because tire would intermittently stop spinning on the stand.

Now that I’m back where I want to be on top speed side wondering if you think I’d see any benefit from trying a different weight slider? I did like the accel curve from the slider a little better, engine seemed to rev more freely, but seems mine were definitely too light at 5.5g. Do you think it’s worth trying a 6/6.5/7g slider? Or if I’m already getting close to rev limiter am I gonna have a tough time squeezing any more accel out of this bike without CDI. Any other worthwhile tips and tricks worth  for this mostly stock Ruck before she hits the streets?

[mtarter]

Also I did take it out for a few laps against my rival stock ruckus and seems mine is consistently pulling a bit harder and hitting slightly higher top speed. I brought the idle down to about 1800 RPM which made it sound much smoother like the other stocker (mine was really loud, almost rattly idling at almost every position between 2000 and 2500). Now im pretty satisfied but if there’s any easy/obvious/cheap way I can keep that top speed and get there a bit faster, I’ll be real happy. Engine doesn’t feel like it’s working too hard getting up to speed on flat ground

[Baizy]

Variator tuning really comes down to preference and feel. I did a couple write ups of so-so quality on some aftermarket variators I have. I had decent enough results with any variator I slapped in if you're considering swapping that out.

I'll focus on your questions now lol.

I personally didn't like the sliders I had (tried a couple weights from 4.5-5.5 and the acceleration curve wasn't right for me and am currently running 5.6G rollers, so I don't reccomend using sliders. That's just me though.

I think getting a CDI is basically saying you want to kill your engine a little quicker, I know I do. Using a CDI usually leads to using lighter weights so that the engine can get into the higher rpms and gain a few mph. I love having the CDI but I would never run a limitless CDI without a tach for fear of straight up throwing a rod between my legs at 50+mph.

If you get setup so that you're bouncing off the limiter you can shave your variator a bit to make the top Gear a little taller, that will theoretically increase your top speed. You just need the power that get there. Hope this all made sense and helps you move forward with your Ruck!

[mtarter]

Just went back and read a bunch of your threads, great stuff. As much as I’d like to try a variator I will probably hold off on that for a bit. And ya everything you said definitely makes sense, I don’t see myself getting the CDI unless the thing is screaming, which it’s not. Finally sending out for my registration this week. Might still try some different sized rollers/sliders while I wait. Also wondering how you liked the airbox mod? What jets did you use with it?

[Baizy]

I REALLY liked the stock airbox mod. That matched with a K&N drop in led to some pretty good airflow while still allowing the mudflap to stay on and the intake to be protected from too much rainwater. I was running a 38/85 setup in the winter 0-5°C at 0-100M of elevation. Was a little rich but I liked the easy starts in the morning and I hadn't got needle shimming figured out quite yet. A 38/80 setup would probably be perfect with the shimming I have now!