Took the 2005 RM85L to Dirtweek. The bike was fitted with a larger rear sprocket, and a Sportech 3" dogbone bar mount system. This allows me to put the bars higher and/or forward, with infinite adjustment intervals (no notches). Great for comfort, although making cables work and installing the kit took a bit of work. Let me know if anyone else is interested in how I did it.
The suspension worked amazingly well! I'm sporting heavier fork springs from MXTech, I think they are .34s, and using the stock rear spring. I'm hitting doubles and tabletops (70') that I really shouldn't be doing on this little bike, and it takes the punishment just fine. Works fine in the woods too, not as plush as the KX but more controlled and less wallowing.
The motor is another thing. It ran great on the tracks, but we went to "the 500" one day on a group woods ride, and I rode like a complete idiot because the thing was sputtering around and wouldn't rev for crap.
Here's what it was doing. I could hold the throttle wide open with the clutch in, and it woud rev up pretty high, then come back down, then sputter around. A properly jetted two stroke should go upstairs, and stay there! While under a load, it would pull pretty well as long as the clutch was out. But if you are on and off the throttle a lot like in the woods, constantly riding the clutch, it sucked. Tried richer and leaner jetting, the BR10 plug looked pretty lean the whole time and the problem stayed about the same. But alas, this is not the stock carb. I had installed a PWK28, in theory a much superior carb to the 80s technology PE roundslide stocker. I consider myself pretty good at jetting, but this thing had me stumped, was starting to think it was the CDI box or something weird, but why does it run well under a steady load?
So, I ended up putting the lame PE stock carb back on, with stock jetting, and lo and behold it runs great! The problem definitely went away. I don't think it pulls quite as hard in the meat of the powerband, but it will panic rev like it should now. By the way, there's nothing quite like knowing you are short on a peaky double jump, trying to panic rev in the air, and having the motor just say "no, I don't think so".
If anyone out there has an idea where I went wrong with the PWK, i'm all ears. The only clues I have...due to the geometry of the situation, the fuel line has to do somewhat of an S curve with the PWK on the RM. Also, I looked up the float level and did adjust it a bit from where it was. No dribbling from the overflow tubes, but yet it seemed to be getting fuel ok, otherwise it shouldn't run right on the track. This carb came off of a KX100 and ran perfect on there.
Looking at the two carbs side by side, the PWK should be a very superior design. The "bell" shaped area on the airbox side is way better for flow on the PWK, plus the advantages of a crescent slide over a round slide.
Even with the carb working right, I wouldn't mind getting a bit more overrev out of the motor, looking for unbiased opinions on exhaust, porting, reeds etc.
Overall, i'm having a lot of fun with this bike!
The suspension worked amazingly well! I'm sporting heavier fork springs from MXTech, I think they are .34s, and using the stock rear spring. I'm hitting doubles and tabletops (70') that I really shouldn't be doing on this little bike, and it takes the punishment just fine. Works fine in the woods too, not as plush as the KX but more controlled and less wallowing.
The motor is another thing. It ran great on the tracks, but we went to "the 500" one day on a group woods ride, and I rode like a complete idiot because the thing was sputtering around and wouldn't rev for crap.
Here's what it was doing. I could hold the throttle wide open with the clutch in, and it woud rev up pretty high, then come back down, then sputter around. A properly jetted two stroke should go upstairs, and stay there! While under a load, it would pull pretty well as long as the clutch was out. But if you are on and off the throttle a lot like in the woods, constantly riding the clutch, it sucked. Tried richer and leaner jetting, the BR10 plug looked pretty lean the whole time and the problem stayed about the same. But alas, this is not the stock carb. I had installed a PWK28, in theory a much superior carb to the 80s technology PE roundslide stocker. I consider myself pretty good at jetting, but this thing had me stumped, was starting to think it was the CDI box or something weird, but why does it run well under a steady load?
So, I ended up putting the lame PE stock carb back on, with stock jetting, and lo and behold it runs great! The problem definitely went away. I don't think it pulls quite as hard in the meat of the powerband, but it will panic rev like it should now. By the way, there's nothing quite like knowing you are short on a peaky double jump, trying to panic rev in the air, and having the motor just say "no, I don't think so".
If anyone out there has an idea where I went wrong with the PWK, i'm all ears. The only clues I have...due to the geometry of the situation, the fuel line has to do somewhat of an S curve with the PWK on the RM. Also, I looked up the float level and did adjust it a bit from where it was. No dribbling from the overflow tubes, but yet it seemed to be getting fuel ok, otherwise it shouldn't run right on the track. This carb came off of a KX100 and ran perfect on there.
Looking at the two carbs side by side, the PWK should be a very superior design. The "bell" shaped area on the airbox side is way better for flow on the PWK, plus the advantages of a crescent slide over a round slide.
Even with the carb working right, I wouldn't mind getting a bit more overrev out of the motor, looking for unbiased opinions on exhaust, porting, reeds etc.
Overall, i'm having a lot of fun with this bike!
