Even to run a 130, they recommend a 3 inch minimum width rim, 3.5 ideally.
they offer these rears that seemed appealing to me:
Size - width - diameter - rim width range
130/70/18 - 133mm/5.2" - 649mm/25.6" - 3-4" (MT3.50)
140/70/18 - 142mm/5.6" - 666mm/26.2" - 3.5-4.5" (MT3.75)
150/70/18 - 154mm/6.1" - 658mm/25.9" - 3.5-4.5" (MT4.25)
I think stock was:
4.00-18 - 116mm/4.6" - 671mm/26.4" - 2.15-3" (MT2.50)
As far as fronts, I have a 19" rim which I now realize it harder to find tires in! The stock front rim width (2.15 also????) seems fine for a 100 or 110 tire, as I didn't remember seeing a 120 in either 18 or 19. I did jot down in my notes that the original front tire diameter if it was a 3.25 as I suspected, was 26.1"/664 diameter. Avon offers:
100/90/19 - 109mm/4.3" - 671mm/26.4"
110/90/18 - 116mm/4.6" - 663mm/26.1"
Both are recommended for a 2.15" rim. If I swap to an 18 and I was right on the original tire diameter, my speedometer it would be the most accurate with the 110/90/18, but maybe I could settle for the 100/90/19 in order not to have to relace my front wheel $$$$$.
The slightly wider tire would be cool & the more accurate speedometer even cooler, but new rims are quite expensive! I may just do a mirror polish on an aluminum rear rim to match the chromed steel front when my rear tire gets bald next year...
Does anyone have any tips on a good affordable sources for aluminum rims? Any feedback on tire sizes?
I don't know if it's worth it to go to a 4.25 rim and run a 150 rear tire, but I do have a GS 1100 swing arm to install on my bike that will give me a little extra clearance. The 140 tire on a 3.5" rim will give me slightly more sidewall angle, but I think it's close enough. According to Avon (&lack of availability of 3.75 rims), seems as if the 130 fits a 3.5" rim perfectly, & the 150 fits a 4.25 rim perfectly. The 140 on a 3.5 is still acceptable by their standards but slightly narrower rim than an exact ideal fit.
Also the other thing that I had it in the back of my mind is at what point would I need offset or spaced out sprockets??? 150 I would imagine is pretty darn close to having chain clearance issues.
As of now I think I'm going to skip the racetech cartridge emulators for the front shocks and invest in 1 or 2 aluminum rims and wider tires to improve handling & appearance.
This will be a 920cc 10:1 GS750 engine w/4-1 exhaust & k&n filters etc. As it is now with the Wiseco 844 kit in it & a half bald Kenda Challenger 110/90/18, I have to be pretty careful on the throttle when turning at lower speeds In order to not start spinning the tire & slide out! I want it to corner better and also have more traction for accelerating, especially in turns!
Feedback on tire size versus handling results is much appreciated, well as tips on what rims and where to buy. Sun & Excel seem to be the only two I see all over. Maybe the swap meet at AMA vintage motorcycle days next summer couldfind me some deals but otherwise I'll expect to be paying a small fortune :-(
Comment