fan

[Jeff Khoury]

Watt-Man's own charts show a 15 degree increase in oil temp on mild highway driving. If you're flogging it like a rented pony, this will be even more severe. Talk to any engineer, you know - the kinds with degrees and stuff, and they will be the first to tell you that heat (especially in the oil) is the enemy. If you live in Icybunghole, Alaska I MIGHT see the use for one. Down here in the lower 48, I think it could do more harm than good. -Jeff Khoury From: "Jeff Saline" To: speedway@... Cc: "DSN KLR650" DSN_KLR650@yahoogroups.com> Sent: Monday, June 20, 2011 7:23:36 PM Subject: Re: [DSN_KLR650] Fan On Mon, 20 Jun 2011 14:56:11 -0000 "speedwaytravelincom" < speedway@... > writes:

> When should the fan start running? At the half way mark, three > quarters or hoter?

<><><><><><> <><><><><><> speedwaytravelincom, I don't know about the 2008 and later models (version II) but the version I (1987-2007) fan switch should turn on at 201 degrees F and turn off at 196 degrees F. Might be helpful to remember the fan switch is located at the bottom or coolest part of the radiator and the temperature sender is located in the head. So the temp on the temp gauge won't be the same as the temp at the fan switch. It'll be significantly warmer. Now just a quick comment about the T-Bob. Up front it might be helpful to know I think it's a good thing for anyone that rides at temps below 70 degrees F. If you always ride in warmer temps I think it's can be helpful. The stock KLR650 cooling system has two issues. It comes with a stat that is 160 degrees with no by-pass so the engine doesn't warm up very fast or to what many experienced techs might consider a good temperature. The cooling system is also limited in its ability to cool by the size of the radiator and capacity of the system. Once the stat is fully opened from the engine reaching that temp the stat no longer is involved in regulating the system temperature. The radiator is now controlling the temp based on air temperature and flow over/through it. The T-Bob addresses the first issue by using a 195 degree F stat and a by-pass system. The 195 degree stat brings the temp higher than the stock stat by 35 degrees F. The by-pass speeds up the heating of the engine by by-passing the radiator about 100% when the stat is closed and maybe by about 15% of the coolant flow (if I recall correctly) when the stat is fully open. So the engine gets hotter faster and then the change in coolant temperature at the engine when cooler coolant from the radiator is introduced when the stat opens is reduced. I think the stock system has a fluctuation of about 80 degrees F with the stat opening and closing. The T-Bob has a change of about 10-15 degrees F. I think Wattman told me the T-Bob might have an engine in hot weather running up to 3 degrees F hotter than a stock system. That's not enough to be concerned about in reality. Best, Jeff Saline ABC # 4412 South Dakota Airmarshal Airheads Beemer Club www.airheads.org The Beautiful Black Hills of South Dakota 75 R90/6, 03 KLR650, 79 R100RT . . __________________________________________________________ Groupon™ Official Site 1 ridiculously huge coupon a day. Get 50-90% off your city's best! http://thirdpartyoffers.juno.com/TGL3141/4e00011646f3af3427st06vuc [Non-text portions of this message have been removed]

[Eddie]

Years ago, I visited an airport where they did a lot of sail plane/ glider flying (Peach State Glider Port, Williamson,Ga). I inquired about the small tow plane having (what appeared to me) a very large oil cooler on the aero engine. My comment of "With a cooler that size, the engine should last a long time" was met with a "not really" response. Seems the engine got really hot going up and cooled rapidly coming back down quickly to take up the next tow. The thermal shock did bad things to the engine. Lycoming apples to KLR oranges, maybe. But: Fast fwd to my once new KLR650 and it's liquid cooled engine. From day 1, I remember watching the temperature gauge "twitch" a lot. It would reach a given point and pause for a bit, drop, go back to the original spot and over again, It was subtle, but noticable. I was not sure why until I read Bill Watson's explainations of how the OEM cooling set up gives little blasts of cold coolant to the ever increasingly hot engine. Wanna warp a piece of hot metal? Hit it with cool liquid. Where's the liquid go through a KLR ? The cylinder & head. Two things you don't ever want to see warp. The thermostat in the Thermo-Bob kit is indeed hotter than what is in the KLR from the factory. However, the coolant overall reaches a more consistent temperature without subjecting the engine to the blasts of colder liquid. If the temp's too high for your taste, I'm sure Bill could help a person source one a few shades cooler and still get the job done. The 'Bobbed KLR650 I have now reaches one spot on the temp gauge quickly and stays there. No more "twitching" from the erratic flow of hot/cold/hot/coolant. At 12,000 miles, it doesn't use oil and never runs hot commuting in 100F traffic. I use Bel-Ray pre-mix cycle coolant and a brand name, motorcycle-specific oil. Your results may vary. eddie in Ga. PS: Manufacturers can and do screw up basic stuff like a cooling system or clutch. I had a 2002 DL1000 with a bad case of the "chudder"{look it up}between 3,500 and 4,500 rpm. I read multiple arguments on the subject saying I wasn't riding it right (lugging, etc...) Really? Me and dozens of others had the exact same issue with their bikes. Suzuki recorded my complaint on the customer (dis)service line and yet a week later had no record of my call. The owner of the selling Suzuki shop test rode it and came back immediately, "That thing ain't right." He called Suzuki and explained it was not operator error. They reluctantly replaced the clutch basket and the problem went away...for a while. They put the same type part in the bike - a part that has since been redesigned. The TL1000 engine it was based upon had no such issues (diff. parts).