heat reduction options - bike heats up if stuck in stop and go traffic for 20 - 30 minutes

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Active Member
Dec 17, 2019
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I have a 2014 vmax1700 with 25K to 30K miles. not sure of the exact miles since the odometer stopped working a few years ago. bike is stock engine wise . some mods in terms of handle bars, rearsets, new painted tins, etc.

so the issue at hand...
-the bike was bought new by me in 2015. since then, its has been my daily driver to go to work. about a 12 mile distance in metro traffic. some times, traffic is bad, and we are crawling at 5 mph or less. when new, this was not a problem...last 2 years...during hot days...the bike will redlight on the temp and sometimes coolant will vocano out .

some observations....
-the lower radiator seems like it takes a good beaten from road debris and/or road tar. I flipped my front fender a few years ago to get more of the fender to protect the lower. I think flipping the finder gets you 2 more inches.
- the bike does cool some if ran for a while afer a period of stop and go...so there is heat transfer.

-the fan always seems to come on late...I have been looking of ra sensor that changes the fan engagement temp to come on sooner..no luck. I did put in a second fan and have a manual switch which helps. also, I changed my drain to brass and could possibly put in a fan sensor there and tie it to the second fan.

- I did a few fin cleanings for both the upper and lower..but no real improvement.

- I did a coolant drain with a supercool type coolant., flush, refill. and after surviving the air burping period...I see a very small improvement. I did find a piece of plastic about 1 inch long. dont know if it was the tip of the plastic drain plug, or if the impeller is made of plastic.

- I replaced the stock radiator cap with a yamaha cap of same PSI/BAR.

- I also added royal purple water wetter.....barley noticable improvement.

- my most recent tweak is replacing the stock radiator cap of 1.1 bar with an aftermarket cap of 1.3 bar. that is supposed to get me 3 more PSI and hopefully give me more time before boil over. this seems to make the biggest difference so far. now it does recover when at the higher end of the heat range instead of going into boil over...but it still runs in the 3/4 + range of the heat dial if exposed to a lot of stop and go.

I have not had any boil overs since the cap and coolant change.

but, I dont have much of a range left on the heat dial...it operates at or above the 3/4 range once it hits stop and go traffic for a while.

if I dont hit stop and go traffic and can keep over 40 mph, the bike stays slightly above the half way mark.

sometimes if I hit a shot period of stop and go....the bike will go to 3/4 but if I can resume cruising speed.....the heat will indicate back down slightly above half way after a few minutes.

so for now....as long as i am in the high 80's and not the 90's and dont hit stop and go...I can make it to work.

some random thoughts

-there seems to be a lot of hot air being sucked in due to vertical rise of heat, during stop and go....was thinking of making some typ of deflector to prevent heat rise from going directly into intake scoops.

- I am wondering if my CAT is clogged causing the heat issues...I have a newer take off CAT that I may swap out.

- my AFR is stock, I know I can cool it down a bit if I richen the AFR and am not opposed to one of the fuel tune solutions.

- not sure if the vmax1700 has an oil cooler, but that would be an interesting option to get a few degrees of cooling added.

-I know I can start swapping out parts...lower radiator...upper radiator...coolant pump....but frankly...theres no scientific analysis approach that would motivate me to spend 700 - 900 dollars replacing these parts before swapping out the CAT, or putting in a fuel tuner.

my thoughts

a. find an oil cooler to get a few more degrees of cooling.
b. swap out the CAT and see if thats improves things. cost is free since I have an extra newer CAT.
c. get rid of the CAT, I have a straight pipe setup I bought used and never installed..it replaces the CAT tub. I didnt install it becuase I did not want to loose the butterfly baffle function in the OEM . that function acts like an engine air brake and has saved my a$# on more than 1 occasion.
d. by a fuel tuner. itching to do this anyway.
e. lower radiator back flush
f. upper radiator back flush
e. replace lower radiator . about 340 dollars.
f. replace upper radiator. another 340 dollars
g. replace water pump. about 150 dollars
h. I know about the mod to by pass the stock heat sensor and will probally do that...but...would like to see what other gains I can pull out of my hat.

the bike runs fine otherwise. I change the oil every years. I probally put 3000 mikes on it yearly.

the heat problem is if the bike gets into stop and go crawling traffic for a while.

when the weather hits mid 90's, I will probably have to switch bikes. I do not think it will make it to work if I hit 20 minutes of stop and go if the weather is in the mid to high 90's.

anyone have any comments that will help prioritize what to do next.

thanks for the input.

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