Hi guys
My 1TX is finished and working fantastically after a top end refreshing process. Even in the running in period I can feel the difference in compression: the cylinders were ovaled
But... the overheating continues. Its true that only in very aggressive sport-riding and uphill on very tight roads, today with 25ºC hot, (that it is even hotter riding on tarmac). But my 3CV don't overheat
Settings: KN replacement filter in OE box, Dynojet kit, std Stage 1 except one shim under the needle, 5º advancer, open cans with STD headers and pan, colder plugs. I've polished head intakes. RPM cooler
My 3CV carry on similar settings, without the shim under the needle, but 4º advancer and open non-std pan and a narrow cooler than Randy's, even wider than OE. The cans are a bit less opened, but not too much (1 cm)
The carburation in both is spot-on, at sea level or 2000 m altitude (not too difficult to check here, 30 km. between both) and now it is possible that my 1TX run faster than my 3CV. Only possible, I've not perform a side to side test. Polishing the intakes has given a turbo-like thrust at 7000 rpm on
We are running off new ideas about the overheating problem. The last 3 are:
1.- Dismount the 5º advancer and fit the OE one
2.- Set the fuel level at maximun
3.- Check the oil pressure...but if the oil pump is 2 in 1, and the part on charge of the cooling is bad, the pressure indication don't say anything, right?
Maybe the fuel level on cubes are not maintained for the vacuum system in extreme situations, hence Yamaha fitted the fuel pump?
And no, it is illegal to fit Unipods in Spain
And yes, I can remove the oil thermometer. But It is not a solution :sarcastic:
Any idea would be welcome. Thanks
Hola, Alf. Jose, from Florida. The overheating occurs at see level or at 2000m ? What size of main jet are you running? According to dynojet #120 main is equivalent to 112.5 mikuni. May be you are a little lean at the top.
How hot?
Quote from: Pat Conlon on March 02, 2020, 04:43:41 PM
How hot?
That's kinda what I was thinking. How is the OP quantifying "hot"?
Joe
Quote from: Tuned forks on March 02, 2020, 06:21:36 PM
Quote from: Pat Conlon on March 02, 2020, 04:43:41 PM
How hot?
That's kinda what I was thinking. How is the OP quantifying "hot"?
Joe
From a previous related thread - he is going off oil temp senders and gauges installed on each bike.
Quote from: Starquest on March 02, 2020, 04:21:52 PM
Hola, Alf. Jose, from Florida. The overheating occurs at see level or at 2000m ? What size of main jet are you running? According to dynojet #120 main is equivalent to 112.5 mikuni. May be you are a little lean at the top.
Thanks
The overheat occurs on sport hard riding going uphill
Dynojet mains have a different design from Mikunis and are not equivalent. Apart that I´ve tested a bigger mains, that dont work, my 3CV would be even learner by that rule, and it is not because the problem is not present
Quote from: Pat Conlon on March 02, 2020, 04:43:41 PM
How hot?
Hi Pat. Happy to chat with you :greeting:
120ºC oil temp in 8 km on an slow, tight road. It is the most extreme condition. Granadilla-Vilaflor TF 21, if you like to have a look on Maps
My 90 model arrives at the end of the road, 15 km, at 115-118ºC, and continuing uphill for the faster road from Vilaflor the temp goes down
Moves:
1.- setting the fuel level at maximun on cubes. Its a pity because the bike runs perfect in any circumstance and altitude
2.- dismount the 5º advancer
3.- fit a fuel pump to maintain the fuel level on cubes
4.- change the oil pump (Maybe the oil cooler part of the pump is not working correctly?)
But in my friend Mingo´s 86 this uphill overheating problem is not present. Yes, the fuel settings are different, but if the problem is the vacuum system no providing enough fuel on uphill roads, the problem will be present too, and it is not the case
I'm running of ideas
Quote from: fj1289 on March 02, 2020, 11:25:56 PM
From a previous related thread - he is going off oil temp senders and gauges installed on each bike.
Yes, right. And both bikes are carefully carb set and tested. And I bought a laser gauge to check temp at the base of the oil filter and to check the accuracy of the digital oil temp gauges
Alf, I remember reading an article a few years ago concerning the FJ and overheating. Apparently it's a common problem and the cause is the cam timing. The fix is to either advance or retard the cams a couple of degrees which cures it and gives better throttle response. Ive been looking everywhere trying to find the article but can't seem to find it. Tony.
Quote from: Bones on March 03, 2020, 01:20:54 PM
Alf, I remember reading an article a few years ago concerning the FJ and overheating. Apparently it's a common problem and the cause is the cam timing. The fix is to either advance or retard the cams a couple of degrees which cures it and gives better throttle response. Ive been looking everywhere trying to find the article but can't seem to find it. Tony.
https://www.hotrod.com/articles/ctrp-9908-building-a-better-engine/ (https://www.hotrod.com/articles/ctrp-9908-building-a-better-engine/)
I also recall another article - but my google skills are failing me right now. As I recall they set the crank the "universal" 105 centers as made popular by Pops Yoshimura
The cars stress these engines so much more than any street driven FJ ever could (assuming it is taken care of and receives basic maintenance)
Quote from: fj1289 on March 03, 2020, 02:14:16 PM
Quote from: Bones on March 03, 2020, 01:20:54 PM
Alf, I remember reading an article a few years ago concerning the FJ and overheating. Apparently it's a common problem and the cause is the cam timing. The fix is to either advance or retard the cams a couple of degrees which cures it and gives better throttle response. Ive been looking everywhere trying to find the article but can't seem to find it. Tony.
https://www.hotrod.com/articles/ctrp-9908-building-a-better-engine/ (https://www.hotrod.com/articles/ctrp-9908-building-a-better-engine/)
My 90 is okay with 4º advancer. Maybe only 1º more, 5º advancer, could be the cause of the overheating?
Firts thing: next saturday I´m going to remove it and check. I will inform
Thanks :i_am_so_happy:
Cam timing modification: I did ask this question 11 years ago, here's the post:
http://www.fjowners.com/index.php?topic=712.0 (http://www.fjowners.com/index.php?topic=712.0)
Speaking of cam timing....Alf, have you verified that your current cam timing is correct?
Sometimes the cam chain can stretch and get the cam timing off....
Pat,
Rereading that cam timing thread brought back old memories, both good and bad.
I think I still have a copy of the FJ cam timing article that Joe Minton wrote for Cycle Magazine back in the '80s.
I did a conversion for your oil temp. 120°C = 248°F. During the summer and riding in my area, the temps easily get to be 95-105°F and the oil temp will often reach 124°C/255°F while sitting in traffic. I have been told by Randy and Robert that these high temps are ok. The Legends racecars often run 127°C/260°F while at WOT on the track. I personally would say things are ok on the 1TX.
Fred
Quote from: FJ_Hooligan on March 03, 2020, 05:22:33 PM
Rereading that cam timing thread brought back old memories, both good and bad.
Yes, that was a tough time for you David. However, you pulled through like the kick ass Texan you are.
We are most fortunate to have you with us.
Quote from: aviationfred on March 03, 2020, 05:30:56 PM
I did a conversion for your oil temp. 120°C = 248°F. During the summer and riding in my area, the temps easily get to be 95-105°F and the oil temp will often reach 124°C/255°F while sitting in traffic. I have been told by Randy and Robert that these high temps are ok. The Legends racecars often run 127°C/260°F while at WOT on the track. I personally would say things are ok on the 1TX.
Fred
Agreed. Randy had some concerns over the oil temps on the race bike - concerned they weren't high enough!
I'm thinking the 3CV May have an issue with running too cool ...
Quote from: Pat Conlon on March 03, 2020, 04:06:45 PM
Cam timing modification: I did ask this question 11 years ago, here's the post:
http://www.fjowners.com/index.php?topic=712.0 (http://www.fjowners.com/index.php?topic=712.0)
Speaking of cam timing....Alf, have you verified that your current cam timing is correct?
Sometimes the cam chain can stretch and get the cam timing off....
Cam chain, guides and tensioner are new
Quote from: fj1289 on March 04, 2020, 12:40:43 AM
Quote from: aviationfred on March 03, 2020, 05:30:56 PM
I'm thinking the 3CV May have an issue with running too cool ...
As far as I know and like Randy has written in another post, 90-115ºC is the optimum oil temperature range
Alf, I am a novice MC enthusiast, (please educate me), however, temp described are chart extreme, but still in range. if in range FINE.
Even 10% out, FINE. As long as the out of range is not too far for too long, so what?
When our bikes were QC checked they ran them from start to red-line then shut down. The bikes didn't even get to temp on start.
The ranges are just a warranty range for service. the bikes will do fine a bit either side for not too long.
I doubt Darko's bike in Croatia (1.3mil km) has run factory temps its whole life
Quote from: fj1289 on March 04, 2020, 12:40:43 AM
I'm thinking the 3CV May have an issue with running too cool ...
This is what i meant
This is the ad i saw, on FJowners whilst not being distracted........
Quote from: Troyskie on March 04, 2020, 04:30:44 AM
This is the ad i saw, on FJowners whilst not being distracted........
The one on the right seems to be running a bit colder than the one on the left!
:rofl2: :rofl2: :rofl2: :rofl2: :rofl2: :rofl2:
Troyskie: Thanks for your coments... and the pic :yahoo:
If I dont own my 3CV I will be not worried... well, not sure. In fact my friend Mingo´s 86-88 run always at the same temperature side to side with my 3cv
His settings: restricted cans (like OE), all STD in carbs except Dynojet needles (yes, with STD mains) and KN filter in OE box
Consider that I´m speaking of extreme ridings. The rest of the time, between 5-10ºC hotter than my 3CV, but ok. In traffic, both dont get 120ºC. This summer, travelling in Andalucia with 45ºC hot, no traffic, secundary order but fast roads (120-160), my 3CV was running at 98-100ºC, better that myself
And yes, I think that I´m going to adopt the Danko solution: no oil temperature gauge :D