Okay, guys, I've been away from MB for a while getting the young adult kids in our family settled into the transitions in their lives including a new granddaughter. Finally have gotten back out on my Blur for the summer, but I need your help.
When I start from any fully stopped position the Blur is hesitating noticeably. My 2007 stock Blur 150 has 2,300 miles on the odometer. It was bought new in 2008 and has had normal oil & spark plug changes, but has had no shop service (valve adjustments, etc).
If you roll on the Blur's throttle just right it will accelerate smoothly, but if you don't it kind of drags until a certain point and then takes off. I need to know where to start to making adjustments to my scooter. Remember, our nearest scooter shop is 4 hours away so I need your help to get my Blur 150 back into normal running condition. You've talked me through scooter repairs on a Buddy 125 & 150 and now the Blur. As always THANKS for your input!
Well, I guess the first thing to determine is whether the engine itself is stumbling, or you're getting some alternating slip-and-grab in the clutch.
The first thing I'd do is run it up to normal operating temperature, put it up on the center stand and see how it reacts to the throttle without much load on the drive train. If there's no hesitation, then it may well be that there's a load of dust and crap in the clutch bell, causing slippage.
If it still bogs while on the stand, then my money would be on the carb - perhaps a partially-clogged jet.
Wish I could see the problem in person as it would probably take only a couple of minutes to get at the root cause.
Why the hell can't everyone live in Jersey? It'd make life so much easier!
charlie55 wrote:
The first thing I'd do is run it up to normal operating temperature, put it up on the center stand and see how it reacts to the throttle without much load on the drive train. If there's no hesitation, then it may well be that there's a load of dust and crap in the clutch bell, causing slippage.
If it still bogs while on the stand, then my money would be on the carb - perhaps a partially-clogged jet.
Hey, Charlie
I went out to the garage tonight to start eliminating what could be up with my Blur scooter. First I threw a new spark plug in it. Then I did what you suggested above. What I found was that the Blur is idling fine on the center stand between 1,900 - 2,000 rpm. So I watched to see when the rear wheel began to spin and it wasn't until I had opened the throttle to 3,000 -3,100 rpm (still on the center stand so no load on the scooter). I also adjusted the Blur's throttle cable via the adjustment nuts just below the throttle. Then I checked the stock air filter, it probably needs replaced. Where can I get one? Other thoughts out there . . . ?
I think clutch engagement at around 3000 RPM is pretty normal, so I wouldn't worry about that. Now, if you let it idle on the center stand, then snap the throttle open (as if you were taking off from a red light), do you still get that stumbling/hesitation?
Would I be off in assuming that you parked it without using some sort of gas treatment over the winter? It seems like that might be the case.
If so, your problems are likely clogged carb passageways.
It might be possible to clear it out with an "Italian Tuneup". Go get some seafoam and pour in the recommended treatment amount (read the directions, a full can is WAY too much). Then take it out and keep gunning the throttle every chance you get. Use your good judgement on how far to push it, the idea is to open up the carb all the way and then slow back down then repeat. Run that tank till empty (doesn't have to be in a single sitting/ride). If that doesn't work, you might have to pull the carb and clean it out.
If it's not a case of non-prepped storage, there might be some other issues involved.
Thanks, for the suggestion, Lostmycage, but you guys have taught me better than that. I always store our scooters for the winter with a full tank of gas and Seafoam added and run them a little. When I get the scoots out in the spring I run some more Seafoam through them. The Blur has already had 3 tanks of gas through it this riding seasoning so I am assuming this is not the issue, but I appreciate you guys helping me eliminate possibilities.
I am thinking I will check my valve clearance next. What is the easiest way to get to the valve cover on the Blur? I have the valve adjustment "How to" for the Buddy 150 and I assume its the same for the Blur, correct? Anything else to know?
Charlie,
Yeah, I just saw the engagement spec this morning of 3,100 rpm in the Blur service manual. I will go back to center stand & try the snap-the-throttle-open procedure and see what happens. I ordered a new air filter from Scooterworks today. Should get here on Friday. I am thinking that besides checking my valves, I should also check my CVT belt. What are the specs & condition of the belt that I need to check for? Also if I'm going to be in the tranny would it be worth my time/$ to get a set of Dr. Pulley sliders (12g) & replace the original ones. Remember the rest of my Blur is stock at the moment.
charlie55 wrote: Now, if you let it idle on the center stand, then snap the throttle open (as if you were taking off from a red light), do you still get that stumbling/hesitation?
Nope - no stumbling or hesitation when snapping the throttle open on center stand. So does this eliminate carb/jetting issues in your thinking?
What I would do now is remover the CVT cover and used some compressed air to blow away whatever dust has accumulated. I would pay extra attention to the clutch bell (that's the outer hub on the rear pulley, with the oval vent holes in it). If you don't want to take it off, at least get in there with the air and give it a good blasting.
At 2300 miles, you really should not be in need of a new belt or sliders. I didn't do mine until about 6500 miles. However, I did need to clean out the CVT innards a couple of time during those 6500 miles. Dust from the belt and clutch pads tends to coat the inside of the clutch bell and the pads themselves, leading to slipping and grabbing when accelerating from a dead stop.
Checking your valves is always a good idea. I do mine at the beginning of each season. So far, they've been spot-on, and I haven't had to do anything with them at all.
Another thing: check the air filter that's within that little black plastic elbow at the front of the CVT cover. It's nothing more than a foam pad, but it sometimes gets clogged with road debris. This'll cut the air flow through the CVT housing and allow the temp to rise, which could shorten the life of your belt.
The belt itself is an oddball size, and I was only able to obtain replacements directly from Scooterworks. I have yet to find any 3rd party or OEM supplier for them. Do yourself a favor and buy a couple now before you actually need them.
I'm with Charlie on this one. It sounds like the behavior is from the CVT and not the carbs because of the way it acts under load (on stand vs moving). If you've ridden it that much and are just now getting the problems, that almost completely rules out anything short of bad gas... but then again it points towards dust build up.
Blurs seem more prone to the build up than the Buddies. It's got a larger case, stiffer Contra spring and the CVT air inlet points out of the air flow, all unlike the Buddy.
If you have a compressor and an air nozzle (and a dust mask and safety goggles) you'll likely have a quick fix. Canned air can work as well, but it's not quite as effective.
You shouldn't need new rollers or a belt at your mileage. If you want to upgrade to sliders you'll be pretty happy with the results. 12g's will give you close to stock performance (slightly better) and 11g's will make it peppy, but not ridiculously so (and you'll stay nearish to your stock gas mileage).
Again, the issues are likely in the CVT, but since you brought it up, the valve check is very similar to the Buddy with a few notes/exceptions. All I had to remove was the seat bucket. I could get to the valve cover from underneath with the bike on the center stand. You can turn the engine to get it to TDC by putting a (please double check the size, it's been a good long while since I did it) 6 point nut (very important not to use a 12 point - it's a nylon hex shaped stud) on the cooling fan's center post and then a ratchet driver and set it to tighten - it's a ton more exact than using the kick start. An inspection mirror (the kind they sell for $2-$3 at parts stores) will help a lot in not needing to remove any other fairing pieces.
One other thing for the valve check: remove the spark plug so that you won't deal with compression in the cylinder, and there'll be less chance of you chewing up the fan's center post.
charlie55 wrote:One other thing for the valve check: remove the spark plug so that you won't deal with compression in the cylinder, and there'll be less chance of you chewing up the fan's center post.
Don't ask......
DAMHIK! (Don't Ask Me How I Know) Recently learned acronym for me, lol.
THANK YOU, GUYS!! I plan to try to pick up a couple of tools & then check the Blur's valves & clean out the CVT housing/filters this weekend. Yes, I will pull the spark plug when I check the valves (did you know that advice is NOT in any of the valve info in the Tech Library, should be don't you think?). I am so grateful for your time & thoughts in responding to my questions. MBers are the best!
The spark plug thing is something that never occurred to me. I know that if you leave the plug in and have the ignition on, turning the fan (which is directly linked to the crankshaft) is like kick starting it... but I think we're operating on the policy of "Don't ask, don't tell".
Okay, gentleman, I just came back from a Blur test drive. I am pleased to report that the scooter is now excelling from a stop without hesitation. Yeah, for your long distance diagnostic skills!
I injured my knee Thursday & it left me hobbled until this morning. Today I cleaned out the CVT housing and clutch bell on the Blur with an air compressor. You guys were right - there was a lot of dust in there that just kept coming out. The belt looked good to me. For the sake of my knee I didn't check the valves today but I will this week. And because it wasn't very difficult to be in the CVT I'm going a step further and ordered 12g Dr. Pulley sliders today.
I think I'll enjoy the smoother, steadier acceleration many scooter riders refer to with these sliders. THANKS GUYS, if you are ever in MN/ND give a shout.
(Oh, Lostmycage, what kind of Blur spare parts? Anything I can use - PM a list if you have one.)
Good to hear that it was something as simple as that. I also followed LMC's advice and changed to 12g Dr. Pulley sliders at the start of this riding season. They do indeed make for smoother and somewhat quicker acceleration. I've lost maybe 1 or 2 MPH at the top end, but that's not even a consideration for the type of riding I normally do.
charlie55 wrote: I also followed LMC's advice and changed to 12g Dr. Pulley sliders at the start of this riding season. They do indeed make for smoother and somewhat quicker acceleration. I've lost maybe 1 or 2 MPH at the top end, but that's not even a consideration for the type of riding I normally do.
Perfect - that's exactly the kind of performance enhancement I'm looking for. Glad I ordered the Dr. Pulley sliders. Picked up an impact wrench yesterday. Will let you know when they are installed.
Wow! I didn't know anything could get here from Taiwan in 5 days, but the Dr. Pulley 12g sliders did. Just got them installed this afternoon. The MB Tech Library posting worked me through this install also. Not difficult at all with the help of the impact wrench.
I was surprised to find that at 2,323 BDU there were 2 original rollers with noticeable flat spots and 2 more rollers beginning to develop them. With that being the case of course I did notice a smoother, more even acceleration from a stop when I took the Blur for a test ride. Can't take the scooter on the highway today to test my top end (40 mph prairie winds), but I'll post if there is a noticeable difference in my top end.
Guess it was a good thing I decided to upgrade to the sliders.
