Search found 10 matches

by fujio001
Thu Oct 24, 2013 1:22 pm
Forum: Performance Technical
Topic: 90/90 Tires
Replies: 20
Views: 11568

Re: 90/90 Tires

Going from the 10x3.00 to 90/90 was a pretty good increase in stability for speeds over 35mph. I believe the ability to fit a 90/90 in the rear also depends on the type of shock you have. On my Sym DD50, I had to dremel the lock ring so it would not cut a groove into the tire. I also placed a washer...
by fujio001
Wed Sep 11, 2013 3:25 am
Forum: Performance Technical
Topic: stroker
Replies: 4
Views: 3496

Re: stroker

Ceramic bearings are harder and not stronger. They are used in road cycling and tests show they really are not faster under load. When improperly matched to soft bearing races, they can actually be slower because they deform the bearing races. What really matters is the roundness of the bearing. Bea...
by fujio001
Fri Sep 06, 2013 12:35 pm
Forum: General Discussion
Topic: seat covers
Replies: 3
Views: 2614

Re: seat covers

I picked up one as well. It is more comfortable and way cooler than sitting on the stock seat.
by fujio001
Wed Aug 28, 2013 3:16 am
Forum: Performance Technical
Topic: Maximizing the potential of a 66cc bore
Replies: 1
Views: 1930

Re: Maximizing the potential of a 66cc bore

Just an update on my Sym DD50. The V8 was just too big for the 66cc. The shop I am working with traded it with a YMS28 and immediately the response was greatly improved. I also changed the variator weights to 6.5 gram Dr. Pulley sliders and the center spring is a red 1k. Clutch springs are 1.5k and ...
by fujio001
Tue Aug 06, 2013 2:49 am
Forum: Performance Technical
Topic: Maximizing the potential of a 66cc bore
Replies: 1
Views: 1930

Maximizing the potential of a 66cc bore

I have a Sym DD50 with a 66cc bore kit, Keli variator, upjetted, V8 exhaust(probably too bigfor my kit) and stock carb. I can get to about 50 mph but it takes some efforts for the last 10mph. Would there be a benefit in the top end by switching to a lightly larger carb like a 17mm or 19mm? With a li...
by fujio001
Sat Jul 27, 2013 9:27 pm
Forum: Technical Help
Topic: Soft Seizing Sym
Replies: 8
Views: 5593

Re: Soft Seizing Sym

The slightly larger carb makes logical sense however I do not think I am maxing it out 35mph even if the gears are stock.
by fujio001
Sat Jul 27, 2013 2:20 am
Forum: Technical Help
Topic: Soft Seizing Sym
Replies: 8
Views: 5593

Re: Soft Seizing Sym

After reading several other threads, could the main jet be too small leading to overheating and seizing?
by fujio001
Sun Jul 21, 2013 3:20 am
Forum: Technical Help
Topic: Soft Seizing Sym
Replies: 8
Views: 5593

Re: Soft Seizing Sym

Aargh! It soft seized again. I was running about 1/64 premix and the stock oil pump. Could it be I am running too lean?
by fujio001
Thu Jul 18, 2013 4:07 am
Forum: Technical Help
Topic: Soft Seizing Sym
Replies: 8
Views: 5593

Re: Soft Seizing Sym

The carb and jet was also changed. To prevent it from happening again I added a couple ounces of oil directly to a full tank of 92 octane. No more issues. I am riding no faster than about 35mph for now. Currently at about 150 miles. I now see the value of having a temperature gauge. Any suggestions ...
by fujio001
Tue Jul 16, 2013 10:28 pm
Forum: Technical Help
Topic: Soft Seizing Sym
Replies: 8
Views: 5593

Soft Seizing Sym

Just got a new Sym DD50. Prior to leaving the shop I had the guys at the shop upgrade the engine to a 66cc big bore kit. They changed a few other things to include the variator and V8 exhaust. On the way home the engine soft seized after 20min of riding. After about 5 min of cooling it started up an...