can anyone answer a few questions on the 4rt. i have one on the way, and would like to know what people think about the following things.

do you need to change clutch master cylinder?

do you need to change rear sprocket? what size

what is the best combination of restrictors in/out?

what is routine maintainence like. any thing to look out for.

any set up tips? tickover etc. ( for expert club level )

any tips on technique for riding them. have read somewhere you have to ride them different to make them grip in mud.

thanks

Hope you enjoy your 4rt as i do mine. My answers:

1) No (but some people i've heard of have changed their thou)

2) I added two more teeth and half a link to the chain

......hope i'm getting paid for these answers dave.....

3) restrictors ALL in

4) oil and filter changed every 6 rides

5) leave the motor alone. i've added a alloy fast action throttle and 6inch bars and some anodised bits but thats it.

6) i position my weight to the rear of the bike.

Edited July 21, 200521 yr by spud

these are my opinions

1. yes change cyl makes clutch less switch like

2. ive tied 43&45 prefer 45

3 front restrictor out only. makes off the bottom softer

4. oil and filter every 4 trials + ive tried low and high idle speeds i thought i prefered low ,now ive had plenty of time on it ive put it back to 1800rpm and will keep it there

5. ride on power & leave clutch alone(easier with low gearing) ive also got 10mm lower and 10mm further back footrest brackets which make a big difference

ive just returned from 4day trial in france and in 40degree heat and 4 hard and long days my bike didnt miss a beat , started and ran fine and used no oil or water.

1. You would be much happier with a 315 clutch master cylinder.

2. Most change to either 43 or 44. I run a 46 and am very pleased with it.

3. I run with all restrictors in. See no reason to change this. Good noise control.

4. Oil (clutch & engine), oil filter every 6 events.

5. I backed off 1/8th turn on idle speed.

6. Use clutch less especially with 46 tooth sprocket.

Runs great and is pretty much maintenance free. Sounds boring but it is a great, easy to ride machine.

ENJOY !!!!

Cut .125 in (2.5mm) off of the clutch actuator to move lever in.

Currently running a 43 but am going to try a 44.

All restrictors out, but made a diverter on the end of a muffler to kill the raspiness.

Installed hebo pegs that move the peg rearward 1 inch (modified).

Edited July 22, 200521 yr by trialsurfer

ive also got 10mm lower and 10mm further back footrest brackets which make a big difference

Munch - did you buy those or did you make up brackets yourself?

ive also got 10mm lower and 10mm further back footrest brackets which make a big difference

Munch - did you buy those or did you make up brackets yourself?

How can i get hold of a set?

1. I resisted older style master cyl. shouldnt have since I like it better

2. I run 43t would like to try 44 or 45

3. all restrictors in and like it that way less wheelspin and noise

4. I change oils every 2 rides but that just me I know that is overkill but I want ot keep OPEC in business!!

5. I put on hebo pegs and taller 6in rise renthals works for me

6. Just practice practice practice and you will come to love it!!

my own fair hands im afraid. i refabricated the standard ones ,looking at them unless you had 2 bikes together youd never know . they are great i tried a few combinations before i chose this as the best.

the Hope 4rts at the ssdt had theirs moved back too I noticed

have you a picture of your pegs you could upload?

well lads,

I'm also considering buying a 4RT , i've ridden one and was well impressed with it But ! the main concern i have is with the maintainance side of things,a friend who has one said the guy who serviced his reckoned it was a pig to service i.e oil and filter because the flywheel had to be removed to get at the filter now i wouldn't be to bad with the spanners but if this job is that awkward and has to be done that often ........mmm makes me wonder should I or shouldn't I But i do really like the bike !Confused , any feedback would be a help.

Hi alan.p

Servicing the 4RT is not as hard as your mates mechanic suggests. You certainly don't have to remove the flywheel to get to the oil filter. My thoughts can be found at Trials Australia forum. http://www.trials.com.au/BB2/viewtopic.php?t=1035

Recently changed my oil and oil filter. The procedure itself was easy and straightforward (no flywheel removal required). Just follow the directions in the manual. The hardest part was removing the crank case gasket. Using a lot of care not to harm the case, I scraped the old gasket off with a razor blade. It took me about an hour. Montesa must use superglue on it. After completing the gasket removal I used a good quality grease to seal everything together. Don't be reluctant to go through this procedure, just be sure to allot some extra time for the gasket removal time.

Rob W & Barcota

Thanks for the advice , servicing doesn't sound as bad as i thought and if the manual is as good as you say we shouldn't have to many problems. p.s Rob , do you really think it would be nessasary to change a piston each year ?

Good question? I would budget on doing it simply because the manual says too. These beasts use very flat, short skirted pistons so there is likely to be a bit more piston wear after one year than with the squarer type pistons used in older four strokes.

Having said that I have seen Honda TL's and Yamaha TY's running on the original pistons 30 years later. But I have also seen Honda CRF 250's (similar bottom ends to 4RTs) lunch a piston and top end after 3 months. (I suspect poor maintenance being the most likely cause, along with high revs.)

It surely depends on how hard and how often you ride the bike. And the maunual doesn't state how many hours of riding can be had from a piston.

It would be far cheaper to replace the piston yearly than to have to rebuild an engine in the event of a piston failure. And better to wear out pistons than the cylinder bore. But if you are an occaisional rider this period could reasonably be extended.

By the way - I am NOT a trained mechanic, but I have built my share of race car and bike engines. So consider what I say but make your own descisions.

Cheers