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I have a Honda DT 125 which I bought for my son to go down the local trail park many years ago. This may become a project in my dotage, the only concern is the sump drain plug has a stripped thread. I have two options to make a new plug with a larger thread but not standard or use some of these Ali brazing rods to fill the hole and tap the hole and use the original plug keeping it standard.

Ive not used these Ali brazing rods are they OK???

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drill it out and retap..............if the alloy is a magnesium alloy you will have a problem welding it........these "laser brand" alloy welding rods can be used with MAPP gas....they are not easy to use....and to block fill that area requires a special type of preparation...and if you get the heat wrong the sump will melt and collapse....

or get someone to tig weld it ...IF it isnt a magnesium alloy

 

 

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3 hours ago, Alex C said:

What about a helicoil ?

 

expensive     non standard thread so you have to buy their tapping kit as well  and nine times out of ten when you undo the bolt / sump bung they whole lot unscrews    have had this problem before with head bolts better to re tap to the next size up and use a dowty washer you will be good to go 

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On 16/11/2019 at 22:42, Saltings said:

expensive     non standard thread so you have to buy their tapping kit as well  and nine times out of ten when you undo the bolt / sump bung they whole lot unscrews    have had this problem before with head bolts better to re tap to the next size up and use a dowty washer you will be good to go 

A little tip to stop this happening is to put some high strength retainer on the helicoil  insert, screw it in and then screw in a bolt with a wrap or two of PTFE tape around it to stop the retainer from sticking to the bolt , and leave it about 4 hours. Loctite 638 is the best.

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6 hours ago, hodge911 said:

sorry but if my memory is correct honda didn't do the dt they done the XL 125 ect and it was Yamaha that done the DT125  

apologies if I,m wrong

You are right, I have an Honda XR400R in the back of the garage and got mixed up. It is a Yamaha DT 125.

Thanks for putting me right.

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On 18/11/2019 at 18:35, strimmer_13 said:

Ahh dt lc's. Excellent bikes, prices are going up. Done many a stupid thing on one of them 👍

Me too, my mates had them, one a orange original DT125 other a Dt175 LC and other lad some mix of 125 &175 top off one engine bottom of another. Great on the sand dunes and along the railway lines from Steetly magnesite to Crimdon dene back along the beach when I was a teen. 

Remember the ypvs power band thing, like mad thing when it kicked in.

Edited by figgy
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15 hours ago, figgy said:

Remember the ypvs power band thing, like mad thing when it kicked in.

OH YESSSSSS !!! 

"Back in the day " my best mate was one of the 1st in the area,to have the lc350 ypvs 

That was the first bike I ever scared myself stupid on .

Whilst overtaking the scholars bus on a large steep hill I dropped a couple of gears and cranked it open and just as I got mid bus all hell broke loose and it climbed up on to the back wheel for the rest of the length of the bus (my best  ever feet on pegs wheelie) I have never been any good at wheelies but that accidentally pulled one had all the kids on the bus thinking I meant to .

When I got off I was buzzing like a bee hive 

Edited by hodge911
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Not shaking and checking your underwear.

A lad once let me have a go of his YZ 490 wound it open along the side of the railway lines in second as it started to lift I dropped it into third, wound it on. Jeez it yanked my arms straight, at that point I couldn't shut the throttle off as could twist my hand I just hung on carapping myself thinking, if I come off here they'll just hide the mess off the big chunky granite stones. Took back rather slowly still shaking. His mate said try my maico 465, no thanks bloody leathal. Lad we knew had a CR500 nearly broke my jaw trying to kick start it, anyone done know what I'm talking about.

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On 18/11/2019 at 19:41, bornfree said:

A little tip to stop this happening is to put some high strength retainer on the helicoil  insert, screw it in and then screw in a bolt with a wrap or two of PTFE tape around it to stop the retainer from sticking to the bolt , and leave it about 4 hours. Loctite 638 is the best.

not had experience of setting helicoids  myself however but the after math for  me  and others / drama by others  / I don't like the helicoids system /   am leaning towards old fashioned engineering  /  right shop will build you od and id  insert which works for a lot less     a 10p phone call to the right person can save a fortune 

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  • 1 month later...

If you havn't already fixed this, I have very successfully repaired a Honda 750 chaincase with Lumiweld (Despite Ditchie's concerns, afaik Honda used a high zinc aluminium alloy, which I found worked well with Lumiweld (a high zinc aluminium alloy)).

I would thoroughly degrease the casing, wash it again with hot detergent, back the hole with a stainless steel plate and, using a MAPP torch, fill it with the lumiweld, using a stout pointed  stainless rod to scratch through the molten pool into the alloy of the crankcase. Then, when cooled, drill and tap.

Edited by amateur
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