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Discussion Starter #1
So on my new build I rode it yesterday and I had my plug back out a little i wasn't worried about it I just figured that the powder coat under the plug that was pushing it out. I dont think it sucked anything in because it was barely out it was just not snug anymore. But then today we went for a small ride not anything crazy just playing and I got back (my brake line broke) and looked it over and it had happened again so I read up and I found that it might be detonation but at this octane and with the different jets I ran yesterday and today( I swapped them to fatter yesterday when it happened then I went back and it happened today) so I dont think it was detonation unless my timing is messed up wich arlan set the timing so I dont think it was that. Or it could be that the threads in the head are loose and now that I'm thinking about it the old plug that came in it had some loctite on it so I'm thinking that if it's not detonation then it's probably the head. That head wasn't going to last anyhow but do you think that that is the problem? I have pictures of the threads I will post soon
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i think it's okay.. just try to clean on your sprak pugs.. use canvas or anything rough cloth.. for clean it.. and put in on fuel.. to clear dust or other dirt.. .. make it clean for make ignition on your machine not blocked.. (y)
 

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ask your builder. builder should know.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
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bdt561 saber
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I do agree with Matuus; call your Builder...since he/she put the engine together, they should know and help you directly.

That plug looks Rich, however; it does not mean it is not detonating. Detonation is the number one cause of SP backing out. To determine detonation, the best method is a full UCCR...search for the UCCR Post BDT made years ago on performing a UCCR....best way to insure you are running correctly.

You can see detonation on top of your piston, in your dome-squish area, on the ceramic, strap and electrode of the SP...with a good Magnifying Loop.

Other possibilities:

SP to loose to threads in head
, note: the threads have to be extremely loose, and even then, if NO detonation is present it won't back out easily or at all....try it on a good engine (with good UCCR, no detonation), you can hand tighten a SP and it will remain as set.

SP Not properly Torqued...again; important if you did not perform a UCCR, and are running on the higher end of the Octane/compression ratio. It also helps to NOT over-tighten SP, and prevents stripping the threads.

Important; if you use a TrQ wrench, make sure the threads are oil free, clean on both SP & Head...oil or any lubricant can change TrQ settings by 30%...causing damage to the aluminum threads.

Also important; if you TrQ your SP, use only the SP manufactures recommended TrQ setting, not a general SP TrQ number. BR8ES is an NGK Plug, TrQ is recommended to 18-21 Lbs for Aluminum....reason being NGK "Crush Washer" requires a specific TrQ to fully tighten correctly...go with NGK Specs, as the Honda Manual TrQ specs are set for Champion SP's only, not NGK.

Note: you don't need a TrQ wrench to set your SP....use a new SP, hand tighten down till it stops, then use a wrench to crush the 'Crush Washer' flat. You will feel when the Crush Washer fully compresses, any tightening beyond 1/4 turn of the Crush Washer being fully Collapsed or Flat, is over-tightening of the SP.

Carlos
 

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Discussion Starter #5
I am running straight 110 mixed at 40:1 with dumonde tech lubricant. And when I thread it in about half way there is a lot of up and down play as well as side to side. And the pictures were of it wiped off with a rag so it was still kinda running rich. But i will call my builder today. And he put the spark plug in and torqued it so it was torqued correctly but the threads in the head are soo loose that it is backing out I think. I have tried another spark plug and no change. I am riding right now so I cant take the head off.
 

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I am running straight 110 mixed at 40:1 with dumonde tech lubricant. And when I thread it in about half way there is a lot of up and down play as well as side to side. And the pictures were of it wiped off with a rag so it was still kinda running rich. But i will call my builder today. And he put the spark plug in and torqued it so it was torqued correctly but the threads in the head are soo loose that it is backing out I think. I have tried another spark plug and no change. I am riding right now so I cant take the head off.
Ask your builder if he performed a UCCR, if not (most likely NO); you should...ask what specs he TrQ the SP to...?

To be clear again; even if the SP is loose, it will not back out if it is NOT detonating, or on the 'verge' of detonation. I have seen dozen's of SP's that wobble severely, extremely loose...they only will back out when the UCCR is set to the high end limits.....110 is only good to 13/1, and even at 11.5/1 with an improper squish, it will detonate and back your SP out.

IMO your problem is NOT loose threads, it is detonation. Set you UCCR & Squish properly and your issues will go away.

PS: Since as you stated your builder put the SP in and TrQ it to the proper specs....don't you agree if the threads are bad or loose he would have noticed and mentioned it you...???

Carlos
 

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Discussion Starter #7
Yeah I think he would have noticed but also with him setting it up I dont think it would have detonation
 

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no uccr. he dont know.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
 

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Yeah I think he would have noticed but also with him setting it up I dont think it would have detonation
no uccr. he dont know.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
Don't just really on what some will tell you on any forum. It's always 'Best' to do your own due diligence, you can easily search for the benefits of UCCR (Un-Corrected Compression Ratio) vs CR (CR aka Compression Ratio)....UCCR is your Best option.

Here are some links to UCCR and VP110, that provide useful information:

Use UCCR to find your Un-Corrected Compression Ratio: UCCR

VP110 is good for up to 12/1: VP 110 - VP Racing Fuels, Inc

VP Fuels are the leaders in Racing Fuels, they clearly rate 110 at 12/1 maximum, Sunoco, Rocket, Dragon Fuels all rate 110 at 12/1 as well....that's because that is all 110 can sustain without detonation occurring, and that is if everything is perfect; UCCR, Squish Velocity, Flame Speed, ect...

Hope this helps,

Carlos
 

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evan. crickets. detonation.


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
 

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Discussion Starter #12
i figured out that it wasnt detonation and i was just being a idiot. i had a 2 stage powder coat on the head and a red top coat and a chrome base so when i went to scrape it off the surface that the spark plug seats i accidentally only took off the red top coat and so the chrome base that i thought was bare metal was actually thick powder that was pushing my plug out.
 

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u check uccr n squish ? whats ur uccr number?


i have the best. bdt built engines.
bdt261 oem
bdt363 prox
bdt431 puma
bdt561 saber
Sent from my iPhone using Tapatalk
 
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