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Which shim stack to use?
Hello suspension experts, I am currently restoring a 1992 kx125 for on-track use and am currently rebuilding the shock. When I bought the bike it cam with 2 shocks so I took apart each. One looks like it was serviced at a shop and the other was stock. I didn't notice the shims were different until both were off and now I don't know which is which or which to use now... here are pictures - The one on the right I think is the modified one... either way it seems to be shorter on both the bottom and top (assuming the top washers are just there to be spacers). Is there anything you know that can steer me in the right direction, or will it not really matter anyway? I'm a beginner mx rider so I don't even know if I would notice... Thanks
2018 upgraded AER fork parts (with Part Numbers)
For those DIY home tuners, here are the parts (See attached image) to upgrade your AER forks (air side only) to the 2018 specs. The job is very simple so long as you have the right tools to dissemble the fork. Keep in mind these parts are reliability oriented and not designed to improve performance. The new "lip" air piston seal seems to be a superior design to the previous "quad" seal as it seems designed to utilize the internal pressures to ensure it maintains the most effective seal possible. Required tools other than a vice, fork cap removal tool and normal size sockets (19mm) and box wrenches Map or propane torch to heat-up and unlock the red Loctite used on the bottom nut of the inner cartridge, and the air piston (Air piston requires a significant amount of heat, don;t forget to remove the seal and bushings before heating) Two large Torx bits to remove the previous air piston and the new air piston (They are different sizes). I don't have the exact sizes at the time of this post, but they are larger than what's sold at your typical home improvement store.   This is the best video on the web to get the job done: BUT NOTE: YOU DO NOT NEED TO REMOVE THE FORK CAP as shown in the video. They only did this to install the MX-TECH A48R cap     https://goo.gl/photos/52mMkdFKwaksVbrv6
Trying to get PDS to work - 19 300 TPI
This may be long, but I will try to break this down in the simplest and most concise manner possible. I'm at my wits end. I'm coming off a 17 300 XC with KYB conversions up front and revalved shock and bladder kit. Suspension has always been phenomenal, no complaints. I've since transitioned to a 19 TPI 300 with PDS and is my first experience racing a PDS bike. I basically put my KYB forks from my XC onto my TPI, no changes to the shock. The first few rides were fairly good, I did not notice many issues. I actually raced the 17 at some faster races like Lake Havasu and other moto/fast events since I did not trust the PDS yet. I eventually got comfortable with the TPI and forgot about doing any other changes. After I got some time on the TPI I made the error of swapping with a buddy with a 250TPI with PDS, suspension done by my same tuner, KYB and everything. It felt so much better that I did not want to ride my bike. When I switched back I realized how bad my suspension was. I had a race the next weekend and convinced him to let me borrow his fork and shock as there was no way I was going to race with my stuff. The race was awesome, bike felt great and had total confidence in the bike with that suspension. Best I've ever ridden. Of course I had to give his stuff back but decided to try to mess with clickers to see if I could improve on the fork and shock before the next race. The next race was disaster. I almost pulled off it was so bad. Probably because I'm not a good tuner and made it worse, go figure. I decided to call my tuner and tell him to give me exactly what my buddy had. Here are some details of what he had vs mine: 52 springs in front vs 48 8.1-8.6 shock vs stock spring Shock has been lowered slightly on his. I'm also 210 6"3 without gear and he is 250 ish 5'11 as well me being a top 30A racer and him a mild 30B. My tuner was somewhat perplexed as it just didn't make sense but I raced with his stuff and loved it. My first test of my copycat suspension was at Revlimiter, which was not the best place to test as I was pushing my bike more than riding it. But at the first harescramble I did the fork was terrible. It deflected, it was harsh and it was plain scary. I spent the next two weeks messing with clickers and sag and any number of things to get the suspension right. It just sucked. It didn't make sense to my tuner or the other guys that run a similar fork. Most fast off-road guys in az run the same valving in the fork. Fast forward to last week. My buddy says, hey, take my suspension again and see if it is as good as you remember. So I did. I went out yesterday and did my same test trails right behind my house. Results: It sucked. fork deflected, wouldn't track, it was scary going around corners as rocks would kick me off the trail, rear felt harsh. I was going out of my mind. A lightbulb went off and I rode home and put the fork on my 17 XC. I already know that suspension was kick ass so why not try to figure out what the variable is, the fork or shock? I used the same front wheel, didn't touch any clickers. Results: Awesomeness. The forks felt fantastic! The forks on the 17 actually felt connected to the ground, as in, if I gave it input it steered. The forks floated over rocks even in turns. I had total and complete confidence. Its the damn shock I need to figure out.  So I switched back to my TPI with the same forks but this time only messed with the shock. I went all the way in on rebound and eventually lower HS and LS compression. After a good hour of doing one change at a time I got the TPI working fairly well, at least rideable and best its ever felt. It still don't have that front end stick that I had with the 17 XC. Ended up a few clicks from full IN at rebound and compression almost all out. I left the fork alone.   If you made it through that, pat yourself on the back. Here are my thoughts: Was lowering the shock a bad idea? Seems like it takes bias off the front and could be the reason it doesn't track like the 17. Is there a good guide somewhere to clickers and what they do? I have real trouble trying to make changes with what I think the bike is doing. I had rebound way to fast in the rear when I thought it needed to be faster. Will the PDS rear ever feel as good as a well set up linkage bike in fast rocky stuff or whoops? In reality, the bike has only been holding me back so far in the rocks, haven't tried it in fast whoops, but that is the next race in a few weeks. I'm used to having a setting and just going out and riding, but I think the PDS needs more careful set up.    Hopefully this gives you an idea of where I'm coming from and makes sense. Thanks for reading and thanks in advance for any input.


Riding a dirt bike after knee replacement
Does anyone here still actively ride trails or off-road after full knee replacement? I know what doctor will say, but not sure what others have done. Ridding now with bad knee hurts but is doable, but after knee replacement not sure what my future holds. Love my bikes, but....
Presentation and injuries from Spain
Hi. Although I have been in this forum since 2013, I have decided to make my first post. Excuse me, but my English level is very basic... I live in Spain. I have been riding a motorcycle for many years, but it was in 2006 when I bought my first enduro bike, a DRZ 400E. Then I had a Yamaha WR 450F from 2010 and finally a Beta Xtrainer 300, because the WR was clumsy and heavy for the enduro form that we practiced. Now I am convalescing from a fall with the Beta, in which I made a fracture-luxation trans scaphoid lunate, in the left hand and a luxation of the acromioclavicular joint in the left shoulder (grade 2). In another post I will talk about it. Regards
check out uhaul's new trailer!
Theyve had a 5x9 open for a while, but its had some things changed so that more or less its a bike trailer. I work for a uhaul dealership and we just got the first of the new breed today! it has drings for straps, a wheel chock built in, and a ramp that folds up and down. Its light weight, stainless steel theres enough room for 2 full size dirt bikes, but only one wheel chock. if my truck can pull it at highway speed, so can yours. the rate for a in town rental (returning it at the dealer you got it from) is 24.95 per 24 hour period.


2005 yfz 450 clutch help
Went riding Saturday and about 60 miles into our annual snirt run after an entire day of the wheeler running flawlessly my clutch lever got alot of play in the last half mile of day then as I came to a stop I noticed the clutch wouldnt disengage. Changed oil the night before, clutch never slipped even a little bit, however the adjustment on the perch and the cable are maxed out from previous owner. It starts in neutral but when I pull the lever in and put it in gear it stalls out. If I start it in gear it jumps forward. Anyone ever have a problem like this? I pretty much know nothing about clutches so any help would be greatly appreciated.
YF60 "4-Zinger" Basket Case Restoration
I'm doing a write-up on a project I'm working on. It's a 1986 Yamaha YF60 "4-Zinger" quad. Maybe some of you all had one as a kid? 😋 I found it on Craigslist for $100 and I couldn't pass it up. It was almost 100% complete; just missing the bottom half of the throttle controls and a CDI box, which I was lucky enough to find on eBay for a decent price. I had to source out a throttle / Off-On-Start assembly from a '86 Tri-Zinger which is basically the same part. It's tough to find parts on-line and there's only a few OEM parts still available for this model.  It has a lighting coil on the stator assembly (OEM parts list calls it a "generator"), but I'm not sure why. It doesn't have any lights on it and it's a pull start so no battery at all. It also has a "pulser" coil? I'm guessing similar to a crank position sensor on a car or truck? On the to-do list: Tear down - paint the frame, high temp / flame-proof paint for muffler assembly New tires - with rigorous searching and cross-referencing I found the size required for the little wheels Restore plastics - sand, prep with adhesion promoter, and apply new decal set (there's a place in Vegas with an eBay store that sells replica sets) Re-cover seat (there's a vendor on eBay that makes replacement covers with the Yamaha branding on the sides) Re-build carb Disable the "Auto Lube" oil pump (going to run pre-mix on it) as the oil tank is gone Oil change Check rear drive shaft assembly and grease Check rear brake / hub Go through electrical and install CDI box Install controls / new grips Top-end service - new piston kit That should bring it back to life and into decent shape. I hope that my son can get some fun out of it until he outgrows the machine. Then I'll sell it to someone who will take care of it and keep it running down the road.
2002 raptor 660 oil tank blew
Let me start off with " don't let your buddies ride your toys ". So I bought a 2002 raptor 660 supposedly with a top end rebuild. Who ever did it, lost a lot of bolts for the body, and broke an exhaust stud. But the real problem happened when I let my buddy take it for a spin down the road. He didn't come back so I drove the truck down the road and I see him waving for me and I took another look and saw oil paInted all over the road. He told me my catch can blew up mid ride in 3rd gear. It broke both the bolts for the mount, and it opened up halfway. Well I double checked it and found the breather hose at the top was plugged with a bolt and hose clamp. Was it too much pressure inside of it that it blew? What do I have to do in the Future so this doesn't happen again?

Inside TT

How to ask questions about dirt bike?
Ok I’m really new on this site and am desperately trying to ask fellow riders a question I’m having about my bike. How do I ask a question for everyone to see?
Does not let me post....
I am unable to post a forum of any sort other than “bug fixes”
Can’t Post Pics From App (iOS 12.1)
Hey TT,   Sorry if I’ve overlooked the article or haven’t searched well enough, but does anyone else have to try desktop mode to post pics in topics?   Seems like the buttons may be hidden near the bottom in the app or something.. any thoughts or input?   -Dave