Friday, March 23, 2012

Mike's 2003 YZ450F Yamaha lowering link question

Mike writes: I am 5’7” tall, and a new dirt rider. I have raced DH mountain bikes for years, and roadraced motorcycles for years, but never spent much time in the dirt on a moto. I just bought a 2003 YZ450F so I can tool around with my 9 year old while he learns. I am normally pretty aggressive on two wheels, but I’m not sure to what extent I will take to it. My problem is that the bike is VERY tall, and I’d like to lower it as much as possible without ruining the handling. I’ll most likely just be trailriding. Does your lowering link for my bike handle properly if I also lower the front by raising the forks in the tripples? How much can I do that, and what will be my net seat lowering? Will there be any ill effects if I also shave the seat as well as using your link and lowering the front?

Our reply: At 180 you may need to go to a heavier spring since you are on borderline with stock setup. The YamaLink's extra leverage would make the bike "think" you are 180 pus about 18 pounds, and before gear that's too heavy with the stock spring.

Many decrease race sag to about 94mm and turn in high-speed compression in 1/4 turn increments. That would work great tooling around following your kid but it would more than likely be too soft and bottom excessively on a MX track or aggressive riding until you put on a heavier spring.

Jim from Colorado has a 2005 Wr250F lowering link question

Jim writes: I have a 2005 wr250f. (steel frame) It handles really nicely at speed but when climbing the slow rocky or loose stuff in 1st gear it looses its line easily and wants to tip due to the top heaviness of the machine. Do you think the lowering link will help significantly with this issue on my bike ? Ideally do some folks get spacers in the front forks to go with the link to lower both ends the same ? I understand this is different than raising the forks in the clamps which changes the rake.

Our reply: Losing the line is a combination of lack of momentum and the rear tire not digging in. The extra leverage of the YamaLink will help tremendously if sag and spring rates are set properly.

I don't know of anyone who puts spacers in their forks. Travel is often decreased and the bike rides more rudely on the small bumps.