Honda TRX250R Forums banner

21 - 36 of 36 Posts

·
Registered
Joined
·
4,109 Posts
we have well over 200 motosmx and alot off tt and wrecks on our 89 with zero cracks.and if a person doesnt have a frame jig to put the frame in while welding most likely they will tweek the frame.also since it's a atv most wont take the time welding small areas at a time and also stiff isnt always good.mild steel is great for not cracking but flexing.after you weld it and heat treat that area there will be no flexing just cracking.
 

·
Registered
Joined
·
12,966 Posts
Best to leave the frame alone, no gussets, repair what needs repairing, and keep it as original as possible; it will be worth a lot more than a gusseted frame.

Carlos
 

·
Registered
Joined
·
239 Posts
Best to leave the frame alone, no gussets, repair what needs repairing, and keep it as original as possible; it will be worth a lot more than a gusseted frame.

Carlos
"Weld rear engine mount to 86-87 TRX250R frame like 88-89" Carlos



So why did you advise a member in another thread to weld a rear motor mount to a frame that did not have one from the factory??????
 

·
Registered
Joined
·
12,966 Posts
"Weld rear engine mount to 86-87 TRX250R frame like 88-89" Carlos



So why did you advise a member in another thread to weld a rear motor mount to a frame that did not have one from the factory??????
First you have to put it in the context of that particular thread, and not taken out of context. "Options" are not all inclusive....what I posted in another thread:

"Couple of options:"
"Cut 88/89 swingarm at pivot bolt are like 85-87, use 'H' bracket"
"Weld rear engine mount to 86-87 TRX250R frame like 88-89"


Obviously you don't know the meaning of "options", you may or not choose any particular option, that is the definition. It doesn't mean an option has to be the 'best' course of action, just an alternative, an "option".

Carlos
 

·
Registered
Joined
·
631 Posts
My stock frame started cracking over 20 years ago. For me it started cracking at welds in the sub frame. Had it welded and repowder coated, the next season it broke in other spots (other spots on sub frame, motor mounts, near the steering stem clamp). No serious mx, racing or crashing. Mostly sand riding.

Most often breaks occur at areas of high stress concentrations (welds, joints, holes..etc). Breaks are often caused because of surface defects, high stress concentration and/or work hardening from cycle loading.

Adding gussets increases material thickness, reduces stress concentrations and changes it's 2nd Moment of Interia. 2nd Moment is important in determining how much a beam will deflect under load. Not only is the material important, but it's cross sectional shape with respect to the load is also important. There is a reason why the I Beam shape is used in building. It helps minimize buckling and deflection under load.

Most manufacturers have made efforts to address some of the problem areas. Looking at changes of OEM dirt bike and Atv frames over the years, there have been improvements especially around the swing arm pivots.

Gussets will make the chassis stiffer. This a preference, some like the chassis to flex a bit more, other prefer ridgid. I personally prefer my chassis not to break and, being a sand rider, I believe there is an advantage to running a chassis with less flex.
 

·
Registered
Joined
·
471 Posts
30+ years of racing quads and never had any cracking issues with a gusseted frame....The weak areas in the TRX250r frame have been well documented so why not use a gusset kit if evidence of cracking is seen??....Ive raced all kinds of racing as well has others on here where gusseting is used on BRAND NEW frames and suspension parts by builders...Most gusseting Ive seen or had done for me is becuse you don't want flex in racing applications....If your frame is flexing or twisting all the time it makes it that much harder to set up a suspension...I'm not a metals guy but I will listen to chassis builders whom some have been building chassis for decades....
 

·
Registered
Joined
·
140 Posts
30+ years of racing quads and never had any cracking issues with a gusseted frame....The weak areas in the TRX250r frame have been well documented so why not use a gusset kit if evidence of cracking is seen??....Ive raced all kinds of racing as well has others on here where gusseting is used on BRAND NEW frames and suspension parts by builders...Most gusseting Ive seen or had done for me is becuse you don't want flex in racing applications....If your frame is flexing or twisting all the time it makes it that much harder to set up a suspension...I'm not a metals guy but I will listen to chassis builders whom some have been building chassis for decades....
Thank you for clarifying this.
 

·
Registered
Joined
·
81 Posts
The weak areas in the TRX250r frame have been well documented so why not use a gusset kit if evidence of cracking is seen??....
I think this is the most significant fact to be considered, I believe the OP said the frame has no cracking.

I believe he was considering it as a “preventative measure.”

Unless I miss understood his original question.

So I guess my question for you is would you do it on a frame that is not cracking and intended for “normal use?”
 

·
Registered
Joined
·
631 Posts
Mine cracked from what I would consider normal use. I raced mx a few times, otherwise strictly play riding in the sand.
 

·
Registered
Joined
·
239 Posts
I would in fact install a gusset kit to a frame with no cracks as a preventative measure. Gusseting in my experience has never caused an issue. A 30+ year old frame is eventually going to crack if it hasn't already. Frames such as the op has obviously have not been used much, therefore it has not cracked yet. One of the frames I have has zero known cracks and I tig welded in a pumashine gusset kit. Like I stated previously...... Strengthening the frame makes it more ridged and is more pleasing to my eye. Lets face it, the factory welds are terrible in appearance!
A gussets job is to distribute a known load and/or stress over a larger area. Plain and simple.
Loren
 

·
Registered
Joined
·
4,109 Posts
mild steel flex's and is less prone to breaking than a stiff frame.my 89 frame has hundreds of mx tt races without one crack with a 250lb rider.i also would never ruin a oem frame with a gusset kit if it wasnt cracked.
 

·
Registered
Joined
·
347 Posts
aint broke. leave alone. easy.


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

·
Registered
Joined
·
239 Posts
"An ounce of prevention is worth a pound of cure"
 

·
Registered
Joined
·
347 Posts
3 pound of weld. a pound of cure. haha


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

·
Registered
Joined
·
81 Posts
The great thing about opinion threads is there does not have to be one answer. I’m sure there are success and failures on each side of this issue. The OP got opinions on both sides.

what a individual decides between
“If it ain’t broke don’t fix it” and
“An ounce of prevention is worth a pound of cure” is a personal decision.
 
21 - 36 of 36 Posts
Top