Absolutely, any good suspension Guy should have no difficulty doing the Compression/Rebound conversion, at minimum cost
Excellent. I'll put Don at ZR1 onto this thread and let him go to town on my suspension. I think Race Tech has something for the rear shock too, but not totally clear on that. Have to check the rear shock bolts too.
The beauty of Racetech they can build the shock exactly to your requirements, they are less expensive than Olins etc & l understand that they are actually better Terry Hay, Shock Treatment rebuilt my shock to best suit my needs, different spring, shims, 5w oil etc - my TR is so much better now
Well, Engineer9K's fix is in progress on my Terra. The local Racetech guru has a copy of what E9K did and is proceeding. We looked at the rear shock and decided to leave it at changing the spring, which is way too stiff. Same up front, and the fork springs are being lightened along with the internal mods. The work should be finished by early next week and then I can get it together for some testing. Maybe I can get some actual sag when it's all done!
After the last trip I did i bottomed out or got very close to it on some drainage swales but not going too fast. Do I need heavier springs?
Are you working with Don on the North side? I had talked to him awhile back and he thought the yami conversion would work well. I'm curious how this mod will work.
Yes, Don at ZR1. My stuff is finished and I will pick it up next week after the holiday, then promptly go try it out. Stand by!
Sounds wicked cool. Maybe one day we could do Box Canyon. I'm hoping to do the South section of the AZBDR as a day trip in the near future. I think my bike and skills are up for the run.
Box Canyon would be a good first easy run on the new suspenders so I'll let you know when it's all together. However, the first part of the AZBDR can be a bit rougher, especially if it includes the sections up to Flagstaff. There is an eleven mile segment near Long Lake that is nothing but embedded boulders. It is marked on the BDR map as Expert Only, bike damage possible, and it is correct for the most part. Not sure of the Expert part, but you need to have no fear of riding on big rocks for distance. I noticed that the AZBDR route is almost exactly what three of us rode when we did Big Dog's Mex to Canada ride two years ago. Best ride I've ever done to date.
A short report on my fork and shock mods following Engineer9K's write up. Don at ZR1 here in Tucson performed the fork internal mods, and lightened the springs front and rear. No changes were made to the rear shock internals. The bike now has some sag! When I get some help I will measure static and rider sag and post the numbers. I went for a short ride today on a local rough road consisting of gravel, rocks, and mild washes. Nothing extreme, meaning it is a regular auto route, though they go pretty slow. The suspension is notably better, and softer now. About half the fork travel was used which means there is plenty remaining for rougher terrain. I will try to get out on the trails soon to see how it goes. For now I'm satisfied with the results.
OK, the verdict is in! Mag00 and I rode Reddington Rd. and Cascabel Rd for a little over 100 miles this morning. Nothing extreme but enough washouts and rocks to simulate the typical TAT miles that I will be doing soon on the Terra. To cut to the chase, SUCCESS! As noted above, our local Race Tech shop followed Engineer9K's write up. I measured the rider sag and it is right in the 33% range, or perfect. I can sure feel it too. The front end now does a much better job, and I think there is about 1" of travel not used today, but then I didn't take any high speed hits either. We did cross some good washouts at speed, so a little is in reserve up front. Much better control. The back end is noticeably improved with just a softer spring. No shock changes. The spring is no longer slamming the back to full extension after compression (over powering the rebound). I have no concerns now about riding the TAT on this bike. It's obviously not as nice suspension wise as my other trail bikes, but it's not bad now!
Great ride, thanks for the pointers I'm going to save up for the conversion and get the new rear spring first. The back spring is what impressed me most, front I didn't really get going fast to try out, but I sure like the idea of both rebound and compression, and it surely was as good or better at slow speeds.
I just thought I would throw out another suspension clanking/knock solution. On a recent trip out to TN to ride dirt roads near the Cherohala Skyway my suspension started making a lot of clunking sounds. We were on a particularly rocky road and the bike started clattering on some of the rougher sections. I was able to make it clunk at stops by putting all of my weight on the front end with a bounce. I've had it since new and never had any issues with front end clunk. We got down the hill to a gas station and filled up. We parked the bikes and I had a snack with my riding buddy as we discussed the clunking sound I had experienced. I walked back to hop on the bike and found a small puddle of oil near the front end. Long story short, there is a hex-bolt at the bottom of the forks that holds on to some of the cartridge internals. This bolt had come loose and was leaking. I pulled the forks back at camp, and refilled to what I thought had been the drain amount when I serviced the forks earlier this year. I had only lost about 50 mils, but it made a difference. I put everything back together and bounced the forks a bit. No more clunk. The next day we hit the dirt again and about 2-3 hours in to the ride the bike started clunking again. I looked for a leak... nothing. After a break I noticed the bike didn't clunk for a good bit, but after a particularly bumpy section it would start clunking. My hypothesis: The oil was foaming, and the foaming was lowering the level in tubes, and causing the clunk. Think of a beer with too much head on it--the amount of liquid in the glass will go up as the foam settles--same on the forks. I pulled the forks at camp again and added more oil that night (maybe 10-20ml) and that was all it needed. Bikes been perfect for 1000+ miles since then on/off road.
OEM fork oils and suspension in general is designed for 128 lb racers who test-design the bike. Depending on what you weigh, heavier front fork oil will keep the rear end from bouncing, make the usd fork work like it should, and feel better than a fork stabilizer. BMW use to put piss thin 5 or 7.5 fork oil in oem. TRY IT! It's cheap too compared to the alternatives. It's different for different fork oils: for motul 125 lbs /10w, 225 lbs /12.5w, 325 lbs/ 15 w. ymmv of course, but you will NEVER feel the technology in your USD forks (esp on the road) until you increase the fork oil. When I first did it on my usd forks, it felt like a $25K BMW on the road! A Honda/Kawasaki shop owner who raced told me because everyone who offered an opinion was wrong on fork oils for usd forks. His ides NOT ONLY made sense, but it worked spectacularly.
The viscosity of the fork oil changes the damping rates - the thicker the oil the slower the damping response Ideally with the correct shim pack the thinner the oil the more efficient & sensitive the suspension is The spring rate determines the suspensions capacity for weight The shim pack determines the suspension damping characteristics
Re: Reddington Rd. A friend and I rode that last year coming back from Mt. Lemon to Mammoth -- he on a XR650L and me on the Terra. We were hustling as is was getting late. Trying to keep pace with him, I was bottoming both front and rear suspension. I wished I was on my old modified DR650 So, thanks for the feedback on the results of modifying your suspension and to Engineer9K. I'll have to look in to doing it to my Terra.
